7Baggers

Ambac Financial Group, Inc
(NYSE:AMBC) 

AMBC stock logo

Ambac Financial Group, Inc., a financial services holding company, provides financial guarantees in the United States, the United Kingdom, Italy, Austria, Australia, France, and Internationally. It offers financial guarantee insurance policies; and credit derivative contracts and interest rate deriv...

Founded: 1971
Full Time Employees: 103
Sector: Financial Services
Industry: Insurance-Specialty

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Quarterly
Annual
    Unit: USD2026-03-31 2025-09-30 2025-06-30 2025-03-31 2024-12-31 2024-09-30 2024-06-30 2024-03-31 2023-12-31 2023-09-30 2023-06-30 2023-03-31 2022-12-31 2022-09-30 2022-06-30 2022-03-31 2021-12-31 2021-09-30 2021-06-30 2021-03-31 2020-12-31 2020-09-30 2020-06-30 2020-03-31 2019-09-30 2019-06-30 2019-03-31 2018-12-31 2018-09-30 2018-06-30 2018-03-31 2017-09-30 2017-06-30 2017-03-31 2016-12-31 2016-09-30 2016-06-30 2016-03-31 2015-09-30 2015-06-30 2015-05-01 2015-03-31 2014-09-30 2014-07-01 2014-05-01 2014-04-01 2014-03-31 2013-12-31 2013-09-30 2013-05-01 2013-03-31 2012-12-31 2012-09-30 2012-06-30 2012-03-31 2011-12-31 2011-09-30 2011-06-30 2011-03-31 2010-12-31 2010-09-30 2010-06-30 2010-03-31 2009-12-31 2009-09-30 2009-06-30 2009-03-31 2008-12-31 2008-09-30 2008-06-30 2008-03-31 2007-12-31 2007-09-30 2007-06-30 2007-03-31 2006-12-31 2006-09-30 2006-06-30 2006-03-31 2005-12-31 2005-09-30 2005-06-30 2005-03-31 2004-09-30 2004-06-30 2004-03-31 2003-09-30 2003-06-30 2003-03-31 2002-09-30 2002-06-30 
                                                                                               
      revenues:
                                                                                               
      commissions
    68,178,000 36,059,000 30,322,000                                                                                         
      servicing and other fees
    9,362,000 4,855,000 4,472,000 4,964,000                                                                                        
      net premiums earned
    20,001,000 17,027,000 16,203,000 15,678,000 5,000 33,000,000 33,000,000 33,000,000 31,000,000 18,000,000 15,000,000 14,000,000 17,000,000 11,000,000 14,000,000 15,000,000 11,000,000 11,000,000 11,000,000 14,000,000 18,000,000 15,000,000 11,000,000 10,000,000 10,466,000 7,833,000 27,758,000 28,730,000 25,640,000 25,836,000 30,883,000 52,989,000 43,152,000 47,613,000 49,867,000 53,218,000 41,402,000 52,800,000 71,535,000 60,879,000  65,718,000 64,831,000 64,831,000  65,013,000 82,547,000 213,517,871,012 70,949,000 113,262,000 100,256,000 103,538,000 113,074,000 103,042,000 94,950,000 112,845,000 102,055,000 99,271,000 91,799,000 110,679,000 143,085,000 167,005,000 125,231,000 184,415,000 238,401,000 177,732,000 196,812,000 228,094,000 282,326,000 325,471,000 186,866,000 209,641,000 194,795,000 221,019,000 216,006,000 208,156,000 198,499,000 210,788,000 194,180,000 205,046,000 218,098,000 193,242,000 199,634,000 183,499,000 189,593,000 165,435,000 159,626,000 151,992,000 134,752,000 122,396,000 113,630,000 
      program fees
    3,644,000 3,590,000 3,497,000 3,652,000 3,506,000 4,000,000 3,000,000 3,000,000 2,000,000 2,000,000 2,000,000 1,000,000                                                                                
      investment income
    2,355,000 2,666,000 2,609,000                                                     5,341,250 9,039,000 7,600,000 4,726,000 6,638,500 8,425,000 8,861,000 9,268,000 12,404,000 18,454,000 19,004,000 20,884,000 50,427,000 63,810,000 56,722,000 84,926,000 110,868,000 120,603,000 107,903,000 105,970,000 104,558,000 107,191,000               
      other
    630,000 2,408,000 -2,146,000                                                                                       1,884,000 2,015,000 
      total revenues
    104,170,000 66,606,000           71,500,000 80,000,000 86,000,000 119,000,000 53,000,000 51,000,000 49,000,000 129,000,000 88,000,000 62,000,000 75,000,000 -70,000,000 216,162,000 89,126,000 100,368,000 51,951,000 134,015,000 150,638,000 174,057,000 132,966,000 172,848,000 126,228,000 67,165,500 145,028,000 106,732,000 16,902,000 87,690,000 230,752,000  155,491,000              94,298,750 25,717,000 148,195,000 203,283,000 60,796,750 361,156,000 381,170,000 -499,139,000 566,601,000 2,689,511,000 -474,432,000 1,129,521,000 -202,236,000 -2,320,433,000 1,331,822,000 -1,562,639,000 -4,788,351,000 -300,984,000 412,580,000 461,829,000 416,930,000 460,307,000 500,925,000 453,942,000 429,748,000 438,260,000 402,879,000 390,820,000 352,131,000 352,026,000 337,380,000 324,434,000 324,985,000 293,732,000 220,401,000 201,975,000 
      yoy
                34.91% 56.86% 75.51% -7.75% -39.77% -17.74% -34.67% -284.29% -59.29% -30.44% -25.27% -234.74% 61.30% -40.83% -42.34% -60.93% -22.47% 19.34% 159.15% -8.32% 61.95% 646.82% -23.41% -37.15%  -89.13%                  55.10% -92.88% -61.12% -140.73% -89.27% -86.57% -180.34% -144.19% -380.17% -215.91% -135.62% -172.28% -95.78% 670.95% 222.80% -438.36% -1248.48% -165.39% -17.64% 1.74% -2.98% 5.03% 24.34% 16.15% 22.04% 24.50% 19.41% 20.46% 8.35% 19.85% 53.08% 60.63%     
      qoq
    56.40%            -10.62% -6.98% -27.73% 124.53% 3.92% 4.08% -62.02% 46.59% 41.94% -17.33% -207.14% -132.38% 142.54% -11.20% 93.20% -61.23% -11.04% -13.45% 30.90% -23.07% 36.93% 87.94% -53.69% 35.88% 531.48% -80.73% -62.00%                 266.68% -82.65% -27.10% 234.36% -83.17% -5.25% -176.37% -188.09% -78.93% -666.89% -142.00% -658.52% -91.28% -274.23% -185.23% -67.37% 1490.90% -172.95% -10.66% 10.77% -9.42% -8.11% 10.35% 5.63% -1.94% 8.78% 3.09% 10.99% 0.03% 4.34% 3.99% -0.17% 10.64% 33.27% 9.12%  
      expenses:
                                                                                               
      losses and loss adjustment expenses
    19,679,000 14,386,000 10,978,000 10,496,000 18,626,000 38,000,000 18,000,000 -1,000,000 18,000,000 -76,000,000 7,000,000 18,000,000                                                                           15,900,000 10,900,000 9,800,000 6,100,000 5,900,000 
      policy acquisition costs
    6,371,000 3,491,000 3,699,000 3,841,000                                                                                        
      general and administrative
    53,155,000 53,710,000 40,540,000                                                                                         
      intangible amortization and depreciation
    12,214,000 9,746,000 9,741,000 9,176,000                                                                                        
      interest
    2,090,000 6,185,000 5,570,000                                                         22,408,500 29,878,000 29,597,000 30,159,000 30,025,000 29,918,000 29,837,000 29,846,000 29,804,000 29,970,000 30,075,000 24,377,000 22,128,000 22,232,000 22,091,000 19,289,000 16,870,000 19,474,000 19,475,000 19,475,000 15,243,000 13,627,000 13,513,000 13,513,000 13,722,000 13,461,000 13,625,000 13,750,000 14,537,000 12,454,000 10,774,000 10,816,000 
      total expenses
    107,514,000 98,685,000 77,931,000 77,863,000 -24,340,000 141,000,000 103,000,000 77,000,000 91,000,000 6,000,000 73,000,000 86,000,000 -16,500,000 -262,000,000 80,000,000 116,000,000 73,000,000 32,000,000 66,000,000 110,000,000 101,000,000 170,000,000 108,000,000 217,000,000 147,107,000 189,233,000 141,578,000 74,087,000 153,963,000 144,330,000 -134,252,000 318,432,000 158,856,000 232,088,000 19,394,250 28,308,000 45,221,000 4,048,000 475,883,000 -55,343,000  -61,089,000                 995,374,000 228,688,500 285,072,000 438,866,000 190,816,000 480,433,000 535,552,000 1,320,490,000 849,821,000 1,060,911,000 751,476,000 -175,563,000 1,228,145,000 384,960,000 193,911,000 180,530,000 172,589,000 132,470,000 163,158,000 173,962,000 152,301,000 146,844,000 211,282,000 141,969,000 138,848,000 106,081,000 107,568,000 106,259,000 108,053,000 105,071,000 112,283,000 42,605,000 43,033,000 
      pretax income from continuing operations
    -3,344,000 -32,079,000 -22,974,000 -15,107,000                                                                                        
      provision for income taxes from continuing operations
    -481,000 -1,241,000 -2,172,000 -617,000                                                                                        
      net income from continuing operations
    -2,863,000 -30,838,000 -20,802,000 -14,490,000                                                                                        
      net income from discontinued operations, net of tax
     -80,890,000 -52,151,000 -30,247,000                                                                                        
      net income
    -2,863,000 -111,728,000 -72,953,000 -44,737,000 -547,088,000 -29,000,000 -1,000,000 21,000,000 -16,000,000 66,000,000 -13,000,000 -33,000,000 174,000,000 340,000,000 5,000,000 2,000,000 -22,000,000 17,000,000 -28,000,000 17,000,000 -14,000,000 -108,000,000 -35,000,000 -280,000,000 66,116,000 -128,429,000 -43,201,000 -20,459,000 -22,159,000  305,704,000 -190,905,000 7,110,000 -125,441,000 -94,891,000 101,438,000 58,355,000 9,415,000 -391,031,000 282,178,000  214,871,000 82,429,000 82,429,000  -208,233,000 156,049,000 504,801,563,711 231,007,000 222,550,000 282,252,000 -256,953,000 -171,000 -813,350,000 253,322,000 -963,198,000 -75,509,000 -102,418,000 -819,246,000 -167,904,250 76,019,000 -57,574,000 -690,062,000 558,124,000 2,188,243,000 -2,368,783,000 -392,200,000 -2,340,817,000 -2,431,222,000 823,134,000 -1,660,343,000 -3,273,924,000 -360,613,000 173,037,000 213,343,000 202,678,000 213,523,000 238,570,000 221,140,000 204,252,000 175,117,000 186,098,000 185,543,000 183,459,000 180,710,000 171,611,000 159,669,000 162,571,000 137,923,000 131,691,000 119,761,000 
      yoy
    -99.48% 285.27% 7195.30% -313.03% 3319.30% -143.94% -92.31% -163.64% -109.20% -80.59% -360.00% -1750.00% -890.91% 1900.00% -117.86% -88.24% 57.14% -115.74% -20.00% -106.07% -121.17% -15.91% -18.98% 1268.59% -398.37%  -114.13% -89.28% -411.66%  -422.16% -288.20% -87.82% -1432.35% -75.73% -64.05%  -95.62% -574.39% 242.33%  -203.19% -47.18% -99.98%  -193.57% -44.71% -196556.77% -135191.81% -127.36% 11.42% -73.32% -99.77% 694.15% -130.92% 473.66% -199.33% 77.89% 18.72% -130.08% -96.53% -97.57% 75.95% -123.84% -190.01% -387.78% -76.38% -28.50% 574.19% 375.70% -878.25% -1715.33% -268.89% -27.47% -3.53% -0.77% 21.93% 28.20% 19.19% 11.33% -3.10% 8.44% 16.20% 12.85% 31.02% 30.31% 33.32%     
      qoq
    -97.44% 53.15% 63.07% -91.82% 1786.51% 2800.00% -104.76% -231.25% -124.24% -607.69% -60.61% -118.97% -48.82% 6700.00% 150.00% -109.09% -229.41% -160.71% -264.71% -221.43% -87.04% 208.57% -87.50% -523.50% -151.48% 197.28% 111.16% -7.67%   -260.13% -2785.02% -105.67% 32.19% -193.55% 73.83% 519.81% -102.41% -238.58%   160.67% 0.00%   -233.44% -99.97% 218422.19% 3.80% -21.15% -209.85% 150164.91% -99.98% -421.07% -126.30% 1175.61% -26.27% -87.50% 387.92% -320.87% -232.04% -91.66% -223.64% -74.49% -192.38% 503.97% -83.25% -3.72% -395.36% -149.58% -49.29% 807.88% -308.40% -18.89% 5.26% -5.08% -10.50% 7.88% 8.27% 16.64% -5.90% 0.30% 1.14% 1.52% 5.30% 7.48% -1.79% 17.87% 4.73% 9.96%  
      net income margin %
    -2.75% -167.74% -Infinity% -Infinity% -Infinity% -Infinity% -Infinity% Infinity% -Infinity% Infinity% -Infinity% -Infinity% 243.36% 425.00% 5.81% 1.68% -41.51% 33.33% -57.14% 13.18% -15.91% -174.19% -46.67% 400.00% 30.59% -144.10% -43.04% -39.38% -16.53% 0% 175.63% -143.57% 4.11% -99.38% -141.28% 69.94% 54.67% 55.70% -445.92% 122.29% NaN% 138.19% Infinity% Infinity% NaN% -Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% -Infinity% -Infinity% -Infinity% Infinity% -1021.43% -293.62% -69.11% -403.01% -276.17% 21.05% -15.10% 138.25% 98.50% 81.36% 499.29% -34.72% 1157.47% 104.77% 61.81% 106.25% 68.37% 119.81% 41.94% 46.20% 48.61% 46.39% 47.63% 48.72% 47.53% 39.96% 46.19% 47.48% 52.10% 51.33% 50.87% 49.21% 50.02% 46.96% 59.75% 59.29% 
      net loss attributable to noncontrolling interest
    -3,988,000 -892,000 254,000                                                                                         
      net income attributable to shareholders
    -6,851,000 -112,620,000 -72,699,000                                                                                         
      continuing operations
    -6,851,000 -31,730,000 -20,548,000 -16,144,000                                                                                        
      discontinued operations
     -80,890,000 -52,151,000 -30,247,000                                                                                -0.01        
      total
    -6,851,000 -112,620,000 -72,699,000 -46,391,000                                                                                        
      net income from continuing operations per share attributable to stockholders
                                                                                               
      basic
    -0.13 -0.67 -0.45 -0.58                                                                                        
      diluted
    -0.13 -0.67 -0.45 -0.58                                                                                        
      net income from discontinued operations per share attributable to stockholders
                                                                                               
      net income per share
                                              1.83 1.83  -4.61 3.46 1.53 5.13 10.3 0.93   -2.68 0.84 -3.18 -0.25 -0.34 -2.71 -0.573 0.25 -0.2 -2.39 1.94 7.58 -8.24 -1.36 -8.65 -8.45 2.86 -11.69 -31.81 -3.53 1.69 2.04 1.58 2.24 2.08             
      basic
    -0.13 -2.35 -1.54 -1.22 -10.48 -0.63 -0.02 0.44 -0.24 1.44 -0.29 -0.73 1.89 7.5 0.11 0.04 -0.42 0.35 -0.63 0.08 -0.31 -2.33 -0.77 -6.07 1.44 -2.79 -0.94 -0.45 -2.27 0.09 6.72 -4.2 0.16 -2.77 -2.09 2.24 1.3 0.21 -8.66 6.26  4.75                                             1.5 1.53 1.3 1.24 1.13 
      diluted
    -0.13 -2.35 -1.54 -1.22 -10.48 -0.63 -0.02 0.43 -0.23 1.41 -0.29 -0.73 1.87 7.41 0.11 0.04 -0.42 0.35 -0.63 0.08 -0.31 -2.33 -0.77 -6.07 1.41 -2.79 -0.94 -0.44 -2.27 0.09 6.7 -4.2 0.16 -2.77 -2.1 2.22 1.29 0.21 -8.66 6.05  4.57                                             1.45 1.48 1.27 1.21 1.09 
      weighted-average number of common shares outstanding:
                                                                                               
      basic
    45,302,933 48,106,069 48,116,503 47,313,012 46,969,708 47,688,986 46,209,250 45,827,076 45,636,649 45,635,373 45,757,234 45,564,276  45,307,019 45,519,093 46,731,459 46,535,001 46,615,552 46,576,673 46,314,049 46,147,062 46,178,730 46,166,666 46,060,324 45,997,694 45,986,043 45,832,297                        302,469,516 302,468,867 302,469,966 302,469,196 302,466,328 302,439,299 302,467,255 302,467,255 302,355,243  302,177,506 290,050,931 288,244,846 287,671,222 288,770,269 287,639,234 287,565,182 251,391,680 287,599,495 287,633,868 142,032,462 102,929,122 102,297,811 102,557,554 104,643,529 106,593,409 106,725,567 106,485,245 106,438,758 108,280,281 107,392,176 109,098,498 110,191,422 109,771,249 108,412,326 107,769,564 106,779,009 106,428,045 106,050,379 105,865,884 106,124,220 
      diluted
    45,302,933 48,106,069 48,116,503 47,313,012 46,969,708 47,688,986 46,209,250 46,348,776 46,540,706 46,810,735 45,757,234 45,564,276  45,846,405 45,685,349 47,359,731 46,535,001 47,044,132 46,576,673 46,858,064 46,147,062 46,178,730 46,166,666 46,060,324 47,020,058 45,986,043 45,832,297                        302,579,254 302,468,867 302,582,276 302,469,196 302,580,597 302,439,299 302,467,255 302,467,255 302,355,243  302,177,506 290,050,931 288,244,846 287,671,222 288,770,269 287,639,234 287,565,182 251,391,680 287,599,495 294,857,435 142,032,462 102,929,122 102,297,811 103,442,086 105,600,555 107,536,339 107,737,122 107,450,639 107,430,787 109,394,985 108,484,035 110,327,148 111,772,811 111,107,367 110,924,314 110,397,003 109,944,141 109,417,451 108,737,211 108,959,876 109,515,722 
      net income from continuing operations per share attributable to shareholders
                                                                                               
      basic
    -0.13 -0.67 -0.45 -0.58                                                                                        
      diluted
    -0.13 -0.67 -0.45 -0.58                                                                                        
      net income from discontinued operations per share attributable to shareholders
                                                                                               
      total revenues and other income
      54,957,000 62,756,000 -85,185,000 114,000,000 105,000,000 103,000,000 75,000,000 74,000,000 62,000,000 58,000,000                                                                                
      commission income
       36,771,000 38,023,000 23,000,000 13,000,000 18,000,000 12,000,000 15,000,000 10,000,000 14,000,000 9,000,000 7,000,000 6,000,000 9,000,000                                                                            
      net investment income
       2,815,000 -101,552,000 38,000,000 36,000,000 42,000,000 40,000,000 30,000,000 35,000,000 34,000,000 23,000,000 11,000,000 -21,000,000 5,000,000 27,000,000 21,000,000 42,000,000 49,000,000 53,000,000 37,000,000 52,000,000 -21,000,000 44,537,000 86,459,000                          92,871,000 84,078,000 93,836,000 112,117,000 113,573,000 81,588,000 87,964,000 71,665,000 64,109,500 69,840,000 69,028,000 117,570,000 135,380,000 134,977,000 122,909,000 100,271,000 112,918,000 126,757,000 130,740,000 123,645,000 123,969,000 115,825,000 113,190,000 112,064,000 72,700,000 120,247,000 116,983,000 113,955,000 109,010,000 110,646,000 104,450,000 102,008,000 89,593,000 88,081,000 86,704,000 80,890,000 79,892,000 76,595,000 75,895,000 73,593,000 
      other revenue
       -1,124,000                                                                                 7,698,000 7,420,000 19,995,000 -6,179,000 8,517,000   
      commission expense
       10,365,000 13,876,000 9,000,000 8,000,000 10,000,000 7,000,000 8,000,000 6,000,000 8,000,000                                                                                
      general and administrative expenses
       38,531,000 -9,834,000 55,000,000 47,000,000 36,000,000 34,000,000 49,000,000 36,000,000 36,000,000                                                                                
      interest expense
       5,454,000 -41,621,000 20,000,000 16,000,000 16,000,000 16,000,000 16,000,000 16,000,000 16,000,000 30,000,000 49,000,000 45,000,000 44,000,000 43,000,000 44,000,000 50,000,000 50,000,000 50,000,000 50,000,000 58,000,000 63,000,000 66,925,000 67,381,000 67,978,000 66,064,000 65,673,000 62,446,000 48,073,000 29,145,000 28,234,000 31,572,000 31,712,000 31,493,000 30,709,000 30,430,000 29,899,000 28,173,000  27,908,000 31,841,000 31,841,000  31,953,000 32,328,000 84,949,947,039 31,817,000 61,785,000 23,165,000 23,358,000 23,268,000 31,855,000 33,839,000 39,246,000 31,131,000 29,646,000 28,069,000 8,594,500 27,492,000 6,886,000                              
      less: net loss attributable to noncontrolling interest
       -1,654,000 -1,361,000 2,000,000      -1,000,000 -250,000                                                                               
      net income attributable to ambac shareholders
       -46,391,000                                                                                        
      other comprehensive income, after tax
                                                                                               
      unrealized gains on securities, net of income tax provision of 645 and 611
       18,606,000                                                                                        
      gains on foreign currency translation, net of income tax provision of 0 and 0
       36,220,000        16,000,000                   32,056,000                                                             
      credit risk changes of fair value option liabilities, net of income tax provision of 147 and
       442,000                                                                                        
      changes to postretirement benefit, net of income tax provision of 0 and 0
                                                                                               
      total other comprehensive income, net of income tax
       55,268,000 -107,390,000 94,000,000  -15,000,000 102,000,000 -53,000,000 8,000,000 36,000,000 -93,000,000 -118,000,000 -126,000,000 -127,000,000 -6,000,000 -23,000,000 27,000,000 -18,000,000 57,000,000 71,000,000 100,000,000 -191,000,000 7,319,000 -3,454,000 71,257,000 -146,540,000 51,971,000 -53,622,000 154,615,000                                                             
      total comprehensive income, net of income tax
       10,531,000 -654,478,000 65,000,000  5,000,000 87,000,000 14,000,000 -5,000,000 3,000,000 -6,000,000 222,000,000                                                                              
      less: loss on foreign currency translation attributable to noncontrolling interest
       -4,252,000 8,074,000 -5,000,000                                                                                      
      total comprehensive income attributable to shareholders
       4,625,000                                                                                        
      net income from continuing operations per share attributable to ambac shareholders
                                                                                               
      basic
    -0.13 -0.67 -0.45 -0.58                                                                                        
      diluted
    -0.13 -0.67 -0.45 -0.58                                                                                        
      net income from discontinued operations per share attributable to ambac shareholders
                                                                                               
      three months ended march 31, 2025 and 2024
                                                                                               
      balance at december 31, 2024
                                                                                               
      total comprehensive income
                  -121,000,000 -125,000,000 -29,000,000 -6,000,000 -2,000,000 -1,000,000        -166,999,000 29,812,000   -167,053,000 48,713,000  -195,798,000 112,580,000 51,118,000 52,212,000 -413,778,000 208,609,000  163,591,000 26,571,000 26,571,000  -6,130,000 248,851,000 516,903,573,681 324,682,000 140,007,000 376,897,000 -84,495,000 267,866,000 -841,737,000 235,891,000                                     
      stock-based compensation
                                                                                               
      cost of shares repurchased
                                                                                               
      cost of shares (acquired) issued under equity plan
                                                                                               
      changes to noncontrolling interest
                                                                                               
      balance at march 31, 2025
                                                                                               
      balance at december 31, 2023
                                                                                               
      balance at march 31, 2024
                                                                                               
      net investment gains, including impairments
        -3,497,000 -1,000,000 4,000,000 1,000,000 -15,000,000 1,000,000 -3,000,000 -4,000,000  14,000,000 7,000,000 10,000,000                                                                            
      net gains on derivative contracts
        -2,984,000 5,000,000  2,000,000 -2,000,000 4,000,000  -4,000,000 5,000,000 37,000,000 29,000,000 57,000,000 3,000,000 5,000,000 -11,000,000 25,000,000 11,000,000 7,000,000 2,000,000 -70,000,000 -9,890,000 -35,412,000 -16,159,000                                                                 
      other income
        7,000,000 10,000,000 16,000,000 3,000,000 4,000,000 2,000,000 2,000,000 3,000,000 5,000,000 1,000,000 1,000,000 2,000,000 8,000,000 8,000,000 7,000,000 5,000,000 1,000,000 2,000,000   141,376,000 -8,908,000 802,000 2,246,000 694,000 2,491,000 -509,000 46,000 467,000 -86,000 -166,000 2,693,000 6,919,000 7,999,000 7,150,000 -1,156,000  -788,000 1,046,000 1,046,000  5,266,000 1,894,000 4,363,999,572 428 -5,134,000 9,498,000 5,536,000 -368,000 36,137,000 64,793,000 -7,032,000 -4,963,000 9,227,000 28,303,000 25,178,250 186,859,000 -30,243,000 -55,903,000 67,422,000 309,922,000 39,221,000 1,723,000 726,000 -2,713,000 2,053,000 8,457,000 3,519,000 -1,291,000 5,649,000 2,856,000 4,520,000 2,655,000 2,930,000 29,454,000 6,161,000 2,859,000 906,000 2,385,000 799,000 1,355,000 -12,219,000 949,000 1,931,000 825,000 472,000 800,000 
      income on variable interest entities
        1,250,000 3,000,000  3,000,000  1,000,000  -1,000,000 7,000,000 -1,000,000 -6,000,000 22,000,000 2,000,000 3,000,000 2,000,000  2,000,000   3,000,000 11,244,000 3,294,000 15,921,000 454,000 1,831,000 577,000 574,000 -4,049,000 -1,219,000 3,701,000 2,026,000 2,057,000 8,987,000 -27,163,000 -21,435,000 52,603,000  6,962,000 9,116,000 9,116,000  -38,148,000 -5,542,000 -48,623,059,707 55,109,000 -86,949,000 38,326,000 884,000 6,137,000 5,536,000 15,220,000 12,809,000 55,008,000 2,353,000  -111,827,000 26,377,000 -38,546,000 -492,704,000                             
      amortization of deferred acquisition costs
        4,000,000 6,000,000 5,000,000 4,000,000 6,000,000 2,000,000 1,000,000 1,000,000                                                                                
      intangible amortization
        -15,398,000 13,000,000 8,000,000 12,000,000 8,000,000 7,000,000 7,000,000 7,000,000 13,000,000 6,000,000 13,000,000 14,000,000 11,000,000 11,000,000 14,000,000 19,000,000                                                                        
      pretax income
        250,000 -27,000,000 2,000,000 26,000,000 -16,000,000 68,000,000 -11,000,000 -29,000,000 88,000,000 342,000,000                                                                              
      provision for income taxes
        2,500,000 3,000,000 2,000,000   1,000,000 2,000,000 4,000,000 1,000,000 2,000,000 1,000,000                                         -481,000 75,011,000 542,000 2,350,000 12,500 65,000 -122,000 107,000 -471,956,000 -34,284,000 573,861,000 671,900,000 1,077,670,000 -640,687,000  -1,130,441,000   59,013,000 75,897,000 81,782,000 83,626,000 88,393,000 80,501,000 78,652,000 51,861,000 74,812,000 66,429,000 61,632,000 63,562,000 59,366,000 56,712,000 57,343,000 43,526,000 46,105,000 39,181,000 
      net income attributable to common stockholders
        -2,000,000 -28,000,000 -1,000,000 20,000,000 -15,000,000 66,000,000 -13,000,000 -33,000,000 175,000,000 340,000,000 5,000,000 2,000,000 -22,000,000 17,000,000 -29,000,000 17,000,000 -14,000,000 -108,000,000 -35,000,000 -280,000,000 66,116,000 -128,429,000 -43,201,000 -20,459,000 -103,845,000 4,313,000 305,704,000    42,384,000 101,474,000 58,647,000 9,415,000                                                      
      unrealized gains on securities, net of income tax provision of 3, 0, 3 and
        8,500,000 37,000,000                                                                                      
      gains on foreign currency translation, net of income tax provision of 0, 0, 0 and 0
        12,750,000 57,000,000 1,000,000  2,000,000 -29,000,000 21,000,000                                                                                 
      credit risk changes of fair value option liabilities, net of income tax provision of 0, 0, 0 and 0
                                                                                               
      changes to postretirement benefit, net of income tax provision of 0, 0, 0 and 0
        -1,250,000  -5,000,000  500,000                                                                                   
      total comprehensive income attributable to common stockholders
        16,500,000 62,000,000  5,000,000 86,000,000 13,000,000 -6,000,000 3,000,000 -6,250,000 222,000,000 -121,000,000 -125,000,000 -28,000,000 -6,000,000 -2,000,000 -2,000,000 42,000,000 -37,000,000 65,000,000 -470,000,000 73,435,000 -131,883,000 28,056,000 -166,999,000 -51,874,000 -49,309,000                                                              
      three months ended september 30, 2024 and 2023
                                                                                               
      balance at june 30, 2024
                                                                                               
      issuance of common stock
                                                                                               
      fair value of nonredeemable noncontrolling interest in beat capital partners at acquisition
                                                                                               
      balance at september 30, 2024
                                                                                               
      balance at june 30, 2023
                                                                                               
      balance at september 30, 2023
                                                                                               
      nine months ended september 30, 2024 and 2023
                                                                                               
      balance at january 1, 2024
                                                                                               
      balance at january 1, 2023
                                                                                               
      less: net (gain) attributable to noncontrolling interest
           -1,000,000                                                                                    
      unrealized gains on securities, net of income tax provision of 0,
          4,000,000  -4,750,000 -23,000,000                                                                                  
      less: comprehensive loss attributable to the noncontrolling interest
            -250,000   -1,000,000 -250,000                                                                               
      three months ended june 30, 2024 and 2023
                                                                                               
      acquisition of noncontrolling interest in subsidiary
                                                                                               
      balance at march 31, 2023
                                                                                               
      six months ended june 30, 2024 and 2023
                                                                                               
      benefit from income taxes
           5,000,000                 2,939,000 28,322,000 1,991,000 -1,677,000 2,211,000 1,995,000 2,605,000 5,439,000 6,882,000 19,581,000 8,832,000 15,282,000 3,156,000 3,439,000 2,838,000   1,709,000 2,344,000 2,344,000   3,249,000 7,513,998,893 594,000 6,857,000 657,000 2,093,000 667,000  300,000                 157,000 -134,282,000                   
      unrealized gains on securities, net of income tax benefit of 0 and 1
           -7,000,000                                                                                    
      gains on foreign currency translation, net of income tax benefit of 0 and 0
           -8,000,000                -46,000,000   14,571,000                                                                 
      credit risk changes of fair value option liabilities, net of income tax benefit of 0 and 0
                                                                                               
      changes to postretirement benefit, net of income tax benefit of 0 and 0
                           -2,000,000   367,000                                                                 
      less: comprehensive (gain) loss attributable to the noncontrolling interest
           -1,000,000         -250,000                                                                           
      net realized gains on extinguishment of debt
                24,000,000  57,000,000     33,000,000          6,000 3,115,000  2,179,000 2,741,000  24,000 3,586,000 1,235,000 1,420,000             165,000  -177,745,000                                      
      three months ended september 30, 2023 and 2022
                                                                                               
      balance at june 30, 2022
                                                                                               
      balance at september 30, 2022
                                                                                               
      nine months ended september 30, 2023 and 2022
                                                                                               
      balance at january 1, 2022
                                                                                               
      sale of noncontrolling interest in subsidiary
                                                                                               
      unrealized gains on securities, net of income tax provision of
              -13,000,000  -59,000,000 -59,000,000 -72,000,000 -105,000,000                                                                            
      three months ended june 30, 2023 and 2022
                                                                                               
      balance at march 31, 2022
                                                                                               
      sale of minority interest in subsidiary
                                                                                               
      six months ended june 30, 2023 and 2022
                                                                                               
      unrealized gains on securities, net of income tax provision of 1 and
               17,000,000                                                                                
      credit risk changes of fair value option liabilities, net of income tax provision of 0 and 0
                                                                                               
      changes to postretirement benefit, net of income tax provision of 0 and, 0
               3,000,000                                                                                
      three months ended march 31, 2023 and 2022
                                                                                               
      balance at december 31, 2022
                                                                                               
      balance at december 31, 2021
                                                                                               
      losses and loss expenses
                -85,250,000 -353,000,000 -12,000,000 24,000,000 -15,000,000 -55,000,000 -26,000,000 8,000,000 9,000,000 83,000,000 16,000,000 117,000,000 37,139,000 -133,480,000 12,407,000 -42,298,000 33,501,000 32,579,000 -247,395,000 209,806,000 66,100,000 135,011,000         -28,698,000 -28,698,000  175,317,000 -140,011,000 -45,101.75 -154,290,000 -12,783,750 -51,135,000 -36,716,000 -18,745,000 741,411,000 -2,320,000 803,648,000 -60,238,000 196,398,000 919,647,000 141,526,000 165,396,000 323,326,000 89,152,000 385,423,000 459,213,000 1,230,847,000 739,830,000 916,414,000 607,702,000 -339,294,000                17,500,000      
      operating expenses
                26,000,000 37,000,000 34,000,000 34,000,000 32,000,000 32,000,000 28,000,000 33,000,000 25,000,000 23,000,000 21,000,000 24,000,000 25,622,000 29,090,000 24,915,000 21,339,000 28,368,000 26,063,000 36,434,000 33,791,000 31,051,000 27,980,000 36,190,000 21,466,000 27,995,000 28,009,000                                 3,389,000 2,392,250 3,164,000 3,117,000 3,288,000 2,498,500 3,119,000               
      gains on foreign currency translation, net of income tax provision of —, —, — and —
                -34,000,000 -58,000,000 -55,000,000                                                                             
      credit risk changes of fair value option liabilities, net of income tax provision of —, —, — and —
                 -1,000,000 1,000,000                                                                             
      changes to postretirement benefit, net of income tax provision of —, —, — and —
                -250,000                                                                               
      three months ended september 30, 2022 and 2021
                                                                                               
      balance at june 30, 2021
                                                                                               
      balance at september 30, 2021
                                                                                               
      pre-tax income
                  6,000,000 3,000,000 -19,000,000 19,000,000 -18,000,000 19,000,000 -13,000,000 -108,000,000 -33,000,000 -287,000,000 69,055,000 -100,107,000 -41,210,000 -22,136,000 -19,948,000 6,308,000 308,309,000 -185,466,000 13,992,000 -105,860,000 -86,059,000 116,720,000 61,511,000 12,854,000 -388,193,000 286,095,000  216,580,000                                                  
      other comprehensive income, after tax:
                                                                                               
      three months ended june 30, 2022 and 2021
                                                                                               
      balance at march 31, 2021
                                                                                               
      changes to redeemable nci
                                                                                               
      gains on foreign currency translation, net of income tax provision of — and —
                   -23,000,000                                                                            
      credit risk changes of fair value option liabilities, net of income tax provision of — and —
                                                                                               
      changes to postretirement benefit, net of income tax provision of — and —
                                                                                               
      three months ended march 31, 2022 and 2021
                                                                                               
      balance at december 31, 2020
                                                                                               
      net realized investment gains
                    1,000,000 3,000,000 -2,000,000 2,000,000 2,000,000 2,000,000 10,000,000 8,000,000 18,471,000 35,860,000 17,233,000 29,413,000 30,201,000 47,148,000 4,862,000 6,150,000 4,180,000 -4,896,000 11,536,000 11,749,000 14,897,000 1,102,000 2,106,000 -5,353,000  54,101,000 10,045,000 10,045,000  3,067,000 16,289,000 4,466,991,838 -10,310,000 -41,593,000 46,060,000 1,480,000 3,162,000 67,067,000 392,000 18,194,000 4,722,000 -2,435,000 -15,000 18,868,250 2,053,000 18,281,000 55,139,000 24,756,000 92,279,000 12,789,000 -742,905,000 -61,456,000 49,378,000 -1,127,000 22,212,000 4,645,000 3,965,000 881,000 440,000 4,243,000 1,329,000 1,892,000 -379,000 303,000 5,013,000 -1,030,000 2,021,000 7,358,000 3,294,000 11,871,000 7,037,000 12,777,000 13,943,000   
      benefit for income taxes
                    3,750,000 2,000,000 11,000,000 2,000,000 2,000,000  2,000,000 -7,000,000                3,917,000      -2,179,000        -211,000                684,251,000                      
      less: net (gain) loss attributable to noncontrolling interest
                    -250,000                  -82,000 -36,000 -292,000  -44,000 -517,000  160,000                                                  
      unrealized gains on securities, net of income tax benefit of —, —, and 1
                    -500,000 -4,000,000                                                                          
      gains on foreign currency translation, net of income tax benefit of —, —, — and —
                    -2,750,000 -19,000,000 1,000,000  -5,000,000 29,000,000                                                                      
      credit risk changes of fair value option liabilities, net of income tax benefit of —, —, — and —
                    -250,000    500,000                                                                       
      changes to postretirement benefit, net of income tax benefit of —, —, — and —
                    -250,000    -750,000                                                                       
      unrealized gains on securities, net of income tax benefit of 1, 1, 1 and 1
                      26,000,000                                                                         
      credit risk changes of fair value option liabilities, net of income tax benefit of —, —, and —
                                                                                               
      less: net gain attributable to noncontrolling interest
                                              -21,000 -21,000  -328,000 107,000                                             
      unrealized gains on securities, net of income tax benefit of and —
                       -24,000,000                                                                        
      gains on foreign currency translation, net of income tax benefit of — and —
                       6,000,000                                                                        
      credit risk changes of fair value option liabilities, net of income tax benefit of — and 1
                       -1,000,000                                                                        
      changes to postretirement benefit, net of income tax benefit of — and —
                                                                                               
      insurance intangible amortization
                        10,250,000 14,000,000 14,000,000 13,000,000 17,421,000 226,242,000 36,278,000 28,982,000 26,421,000 23,242,000 28,636,000 45,690,000 33,471,000 37,525,000 40,152,000 44,553,000 39,013,000 50,890,000 39,680,000 38,088,000  37,432,000 41,908,000 41,908,000  36,256,000 31,714,000 99,657,937,575 37,473,000                                           
      unrealized gains
                        250,000 42,000,000   31,285,000 15,238,000 56,163,000 -152,250 151,000 -308,000 -452,000 45,000 5,490,000 853,000 1,351,000 1,507,000 3,722,000 12,614,000 35,259,000 9,886,000  -2,918,000 6,820,000 6,820,000  -1,936,000 6,607,000 183,090,925,240 29,614,000 172,813,000 10,278,000 -26,464,000 24,496,000 -10,488,000  24,518,000 676,000 20,063,000  701,740,750 4,550,000 2,979,476,000 -177,063,000 781,659,000 2,865,761,000 6,016,000 1,539,227,000   961,580,000                      
      unrealized gains on securities, net of income tax benefit of 1, , 1 and
                          104,000,000                                                                     
      gains on foreign currency translation, net of income tax benefit of 0, 0, 0 and 0
                          -2,000,000  -23,570,000 -18,533,000  -7,451,500 -8,873,000 -52,989,000                                                              
      credit risk changes of fair value option liabilities, net of income tax benefit of , 0, 0 and 0
                          -1,000,000                                                                     
      changes to postretirement benefit, net of income tax benefit of 0, 0, 0 and 0
                            -322,000 -322,000  -366,000 -303,000 -302,000                                                              
      unrealized gains on securities, net of income tax benefit of and
                           -146,000,000                                                                    
      credit risk changes of fair value option liabilities, net of income tax benefit of 1 and 0
                           3,000,000                                                                    
      other-than-temporary impairment losses:
                                                                                               
      total other-than-temporary impairment losses
                            -42,000  -29,000 -1,643,000 -266,000 -1,010,000 -341,000 -25,664,000 -1,763,000 -21,154,000 -6,844,000 -15,906,000 -18,880,000 -48,070,000 -31,743,000 -1,391,000  -10,361,000 -6,997,000 -6,997,000  -9,051,000 -10,392,000 -47,417,959,443 -38,553,000   -1,355,000 -2,501,000 -7,492,000 -4,311,000 -53,121,000 -17,729,000 -17,793,000 -1,713,000 -12,426,500 -8,461,000 -7,777,000 -33,468,000 -135,330,000 -32,529,000 -675,394,000                          
      portion of other-than-temporary impairment recognized in other comprehensive income
                               -16,000  -4,000 42,000 12,154,000  17,212,000 4,653,000 13,053,000 11,439,000 38,736,000 22,593,000 371,000  7,242,000                                                  
      net other-than-temporary impairment losses recognized in earnings
                            -42,000  -29,000 -1,659,000 -266,000 -1,014,000 -299,000 -13,510,000 -1,763,000 -3,942,000 -2,191,000 -2,853,000 -7,441,000 -9,334,000 -9,150,000 -1,020,000  -3,119,000 -5,011,000 -5,011,000  -8,754,000 -10,392,000 -46,763,959,961 -38,037,000   -237,000 -354,000 -2,328,000 -3,071,000 -34,482,000 -10,070,000 -17,578,000 -1,713,000 -11,355,000 -6,584,000 -7,487,000 -31,349,000 -118,054,000 -32,529,000 -675,394,000                          
      less: loss on exchange of auction market preferred shares
                                                                                               
      credit risk changes of fair value option liabilities, net of income tax benefit of (15), 40, 50 and 82
                            -74,000                                                                   
      credit risk changes of fair value option liabilities, net of income tax benefit of 33, (188), 65 and 42
                             163,000                                                                  
      net investment income:
                                                                                               
      securities available-for-sale and short-term
                              46,552,000 48,247,000 49,985,000 61,742,000 110,551,000 80,999,000 80,943,000 73,150,000 79,169,000 79,530,000 64,368,000 57,982,000 65,619,000 62,278,000  63,332,000 82,881,000 82,881,000  76,882,000 68,807,000 142,865,919,013 51,776,000 57,254,000 85,612,000                                         
      other investments
                              8,290,000 -10,764,000 8,347,000 4,920,000 -311,000 6,178,000 4,217,000 8,409,000 11,702,000 11,387,000 6,390,000 2,839,000 -1,424,000 2,475,000  9,651,000 700,000 700,000  3,211,000 1,994,000 3,580,002,665 350,000 4,123,000 -543,000                                         
      total net investment income
                              54,842,000 37,483,000 58,332,000 66,662,000 110,240,000 87,177,000 85,160,000 81,559,000 90,871,000 90,917,000 70,758,000 60,821,000 64,195,000 64,753,000  72,983,000 83,581,000 83,581,000  80,093,000 70,801,000 146,445,921,678 52,126,000 61,377,000 85,069,000                                         
      credit risk changes of fair value option liabilities, net of income tax benefit of 32 and 230
                              156,000                                                                 
      change in fair value of credit derivatives:
                                                                                               
      realized gains and other settlements
                               74,000 99,000 91,000 106,000 134,000 1,134,000 199,000 201,000 226,000 233,000 252,000 1,693,000 407,000  419,000 596,000 596,000  717,000 775,000 9,777,992,346 1,580,000 7,269,000 2,509,000 4,442,000 2,944,000 3,073,000 3,254,000 3,625,000 3,829,000 4,224,000 5,323,000 -690,627,250 4,862,000 -2,777,295,000         16,973,000                     
      net change in fair value of credit derivatives
                               -78,250 250,000 -217,000 -346,000 179,000 6,624,000 1,052,000 1,552,000 1,733,000 3,955,000 12,866,000 36,952,000 10,293,000  -2,499,000 7,416,000 7,416,000  -1,219,000 7,382,000 192,868,917,586 31,194,000 180,082,000 12,787,000 -22,022,000 27,440,000 -7,415,000 -7,222,000 28,143,000 4,505,000 24,287,000 -8,903,000 15,746,000 9,412,000 202,181,000 -167,139,000 133,210,000 2,132,904,000 963,000 1,545,850,000 -594,359,000 -2,705,179,000 976,615,000 -1,708,199,000                     
      net gains on interest rate derivatives
                               13,004,750 17,333,000 9,149,000 25,537,000 3,984,000 34,068,000 -1,514,000                                                          
      less: exchange of auction market preferred shares
                               20,421,500 81,686,000                                                               
      unrealized gains on securities, net of income tax benefit of (625), 0, (1,211) and 0
                               45,921,500 60,807,000                                                               
      credit risk changes of fair value option liabilities, net of income tax benefit of 40, 0, 82 and 0
                               137,000 340,000                                                               
      unrealized gains on securities, net of income tax benefit of 1,122, 0, (586) and 0
                                 575,000                                                              
      credit risk changes of fair value option liabilities, net of income tax benefit of (188), 0, 42 and 0
                                 -906,000                                                              
      unrealized gains on securities, net of income tax benefit of (1,708) and 0
                                  122,304,000                                                             
      credit risk changes of fair value option liabilities, net of income tax provision of 230 and 0
                                  1,114,000                                                             
      changes to postretirement benefit, net of income tax of 0 and 0
                                  -859,000                                                             
      total comprehensive income attributable to ambac financial group, inc.
                                  460,319,000 -167,053,000 48,713,000 -89,226,000 -195,600,000 112,616,000 51,410,000 52,212,000 -413,462,000 208,728,000  163,757,000    -5,994,000 248,698,000 516,879,573,590 426,410 139,895,000 376,985,000 -83,886,000 267,920,000 -839,322,000 235,858,000                                     
      net income attributable to common shareholders
                                   -190,905,000 7,110,000 -125,441,000     -390,987,000 282,695,000  214,711,000 82,450,000 82,450,000  -207,905,000 155,942,000 505,218,563,344 230,975,000 222,920,000 282,299,000 143,576,000 157,544,000                                       
      unrealized gains on securities, net of deferred income taxes of 0
                                   -434,000 12,649,000 21,335,000 -64,780,000 24,719,000 48,170,000 59,791,000 8,382,000 -113,839,000  -17,448,000 -17,225,000 -17,225,000        97,142,000 108,446,000 36,466,000 -20,904,000                                     
      gains on foreign currency translation, net of deferred income taxes of 0
                                   24,624,000 29,292,000 12,593,000 -35,872,000 -13,323,000 -55,152,000 -17,781,000 -30,909,000 40,490,000  -33,805,000 -38,429,000 -38,429,000                                                
      changes to postretirement benefit, net of tax of 0
                                   -338,000 -338,000 2,287,000 -255,000 -254,000 -255,000 787,000 -220,000 -220,000  -27,000 -204,000 -204,000  -204,000 -204,000                                             
      total other comprehensive income, net of tax
                                   23,852,000 41,603,000 36,215,000 -100,907,000 11,142,000 -7,237,000 42,797,000 -22,747,000 -73,569,000  -51,280,000 -55,858,000 -55,858,000  202,103,000 92,802,000 12,102,009,970 93,675,000 -82,543,000 94,645,000 97,245,000 110,493,000 -28,387,000 -17,431,000                                     
      less: comprehensive (gain) loss attributable to the noncontrolling interest:
                                                                                               
      net gain
                                              -21,000 -21,000  -328,000 107,000     -100,663,750 157,373,000                                       
      derivative products
                                      83,992,000 -14,510,000 -36,331,000 -83,424,000 -65,083,000 50,999,000  -37,774,000 -15,685,000 -15,685,000  -47,985,000 -53,841,000 114,770,903,915 12,372,000 115,340,000 -569,000 -11,863,000 -36,007,000 -124,091,000 46,957,000 -20,456,000 -215,774,000 -65,592,000 21,004,000 -51,888,000 -78,368,000 -70,957,000 -58,227,000 73,658,000 -222,450,000 -44,219,000 -14,199,000 -31,963,000 -16,878,000 -15,137,000 -68,820,000 -409,000 1,216,000 2,464,000 3,606,000 5,379,000 3,252,000 3,321,000 4,686,000 2,555,000 8,896,000 -3,759,000 8,813,000 10,452,000        
      losses and loss benefit
                                      -56,745,250 -69,204,000 -52,496,000 -105,281,000 -133,213,000 -147,477,000                                                    
      goodwill impairment
                                          514,511,000                                                     
      net (gain) loss
                                      -82,000 -36,000 -292,000  -44,000 -517,000  160,000                                                  
      currency translation adjustments
                                          -272,000 398,000  -326,000 -395,000 -395,000  192,000 46,000 440,999,724 414,000 482,000 -41,000 -171,000 117,000 -183,000 31,000                                     
      less: comprehensive gain attributable to the noncontrolling interest:
                                                                                               
      underwriting and operating expenses
                                          25,006,000 25,873,000  24,523,000 25,513,000 25,513,000  24,033,000 25,786,000 68,768,958,736 25,047,000 34,340,000 34,429,000 35,581,000 33,347,000 33,567,000 36,534,000 46,753,000 40,340,000 11,836,000 42,376,000 37,656,750 41,200,000 58,931,000 50,496,000 42,273,000 28,039,000 48,861,000 56,637,000 58,365,000 46,896,000 61,953,000 48,982,000 34,954,000 34,576,000 33,438,000 36,376,000 33,781,000 30,192,000 31,871,000 37,896,000 27,870,000 27,844,000 28,692,000 33,403,000 26,157,000 29,246,000 25,654,000 23,795,000 21,013,000 22,166,000 18,467,000 18,603,000 
      pre-tax income before reorganization items
                                          -388,193,000 286,095,000  216,580,000                                                  
      reorganization items
                                              2,000 2,000  186,000 23,000 492,999,572 4,000 -1,566,000 2,059,000 2,735,000 1,252,000 767,000 2,461,000 10,067,000 8,519,000 6,470,000 24,805,000                                 
      net realized losses on extinguishment of debt
                                           -1,246,000  -93,000                                                  
      losses and loss
                                             -150,952,000                                                  
      portion of loss recognized in other comprehensive income
                                              1,986,000 1,986,000  297,000  653,999,482 516,000   1,118,000 2,147,000 5,164,000 1,240,000 18,639,000 7,659,000 215,000  1,071,500 1,877,000 290,000 2,119,000                             
      total revenues before expenses and reorganization items
                                              155,339,000 155,339,000  57,333,000 109,138,000 581,047,585,933 171,652,000 289,621,000 291,427,000 170,352,000 197,162,000 -5,961,000 324,136,000                                     
      total expenses (benefit) before reorganization items
                                              70,564,000 70,564,000                                                
      pre-tax income from continuing operations before reorganization items
                                              84,775,000 84,775,000  -210,226,000 159,321,000 512,808,562,176 231,605,000 227,841,000 284,968,000 148,129,000 159,292,000 -812,794,000                                      
      pre-tax income from continuing operations
                                              84,773,000 84,773,000  -210,412,000 159,298,000 512,315,562,604 231,601,000 229,407,000 282,909,000 145,394,000 158,040,000 -813,561,000      -63,433,000 76,084,000  -689,955,000 86,168,000 2,153,959,000 -1,794,922,000 279,700,000 -1,263,147,000 -3,071,909,000                       
      total comprehensive income attributable to common shareholders
                                              26,987,000 26,987,000                                                
      net income per share
                                              1.83 1.83  -4.61 3.46 1.53 5.13 10.3 0.93   -2.68 0.84 -3.18 -0.25 -0.34 -2.71 -0.573 0.25 -0.2 -2.39 1.94 7.58 -8.24 -1.36 -8.65 -8.45 2.86 -11.69 -31.81 -3.53 1.69 2.04 1.58 2.24 2.08             
      net income per diluted share attributable to common shareholders
                                              1.77 1.77                                                
      total expenses before reorganization items
                                                 267,559,000    61,780,000 6,459,000 22,223,000 37,870,000 806,833,000 68,053,000 872,181,000 17,696,000 243,601,000                                  
      unrealized gain on securities, net of deferred income taxes of 0
                                                 185,163,000 88,722,000 -41,909,962,894 53,877,000 -136,008,000 94,098,000                                         
      gain on foreign currency translation, net of deferred income taxes of 0
                                                 17,144,000 4,284,000 43,164,972,864 39,798,000 43,426,000 -261,000 -115,000 1,686,000 -5,324,000 3,213,000                                     
      net income per diluted share attributable to ambac financial group, inc. common shareholders
                                                 -4.61 3.31 1.51 4.98 9.98 0.93   -2.68 0.84 -0.825 -0.25   -0.573 0.25   -0.498 7.58                           
      total (benefit) expenses before reorganization items
                                                  -50,183,000 -5,939.25 -59,953,000                                           
      other loss
                                                    -1,751,000                                           
      less: net income attributable to the noncontrolling interest
                                                   -416,999,633 32,000 -370,000 -47,000   -2,232,000  11,250 -2,000 14,000 33,000 -3,250 13,000 -15,000                              
      amortization of postretirement benefit, net of tax of 0
                                                     202,000 808,000                                         
      less: comprehensive income attributable to the noncontrolling interest:
                                                                                               
      total comprehensive income attributable to ambac financial group, inc
                                                    324,236,000                                           
      other-than-temporary impairments:
                                                                                               
      less: net gain attributable to the noncontrolling interest
                                                       -275,000 -171,000  2,000                                     
      other comprehensive loss after tax:
                                                                                               
      income
                                                       -100,663,750 157,373,000                                       
      less: reclassification adjustment for net gain included in net
                                                       13,779,000 -361,000                                       
      amortization of postretirement benefit, net of tax
                                                       -948,000   -3,792,000                                     
      income per share attributable to ambac financial group, inc. common shareholders
                                                       -0.33 0.52                                       
      income per diluted share attributable to ambac financial group, inc. common shareholders
                                                       -0.33 0.52                                       
      loss attributable to common shareholders
                                                         -811,118,000                                      
      less: reclassification adjustment for net gain included in net income
                                                         59,529,000 -4,052,000                                     
      unrealized losses
                                                          -10,476,000    -14,226,000         -657,710,500 -1,867,250,000  -1,725,172,000                     
      pre-tax gain from continuing operations before reorganization items
                                                          256,083,000 -219,869,000 8,021,000                                   
      pre-tax gain from continuing operations
                                                          253,622,000 -229,817,500 -498,000                                   
      net income attributable to common shareholders.
                                                          253,320,000                                     
      financial guarantee:
                                                                                               
      financial services:
                                                                                               
      net mark-to-market losses on non-trading derivative contracts
                                                                                               
      corporate and other:
                                                                                               
      net realized gains
                                                               2,543,000 -521,000 10,693,000                              
      interest from investment and payment agreements
                                                           1,539,500 1,943,000 2,024,000 2,191,000 3,435,500 3,951,000 4,357,000 5,434,000 6,598,000 6,433,000 8,311,000 12,789,000 38,012,000 50,048,000 57,914,000        98,048,000 81,935,000 77,348,000 70,854,000 64,416,000 57,681,000 48,452,000 45,740,000 52,350,000 47,227,000 55,476,000 58,996,000   
      other expenses
                                                           2,010,000 2,719,000 2,707,000 2,614,000 2,552,750 3,460,000 3,124,000 3,627,000 7,352,000 3,316,000 3,541,000 3,951,000 35,600,000 3,466,000         3,303,000 3,572,000 3,521,000 2,912,000 3,431,000 3,819,000 3,349,000 3,381,000 3,695,000 6,780,000 6,234,000 6,158,000   
      net income attributable to ambac financial group, inc.
                                                           -249,304,500 -75,507,000   -63,596,000 76,006,000   -143,181,000 2,188,257,000                           
      pre-tax loss from continuing operations before reorganization items
                                                             -95,406,000 -792,091,000                                 
      pre-tax loss from continuing operations
                                                             -101,876,000 -816,896,000   -57,696,000                              
      net loss attributable to ambac financial group, inc.
                                                             -102,432,000 -819,279,000   -57,559,000 -690,051,000   -2,368,794,000 -392,187,000                         
      net loss per diluted share attributable to ambac financial group, inc. common shareholders
                                                             -0.34 -2.71   -0.2 -2.39   -8.24                          
      loss on variable interest entities
                                                              -6,125,000                                 
      net change in fair value of total return swap contracts
                                                                    6,902,000 22,052,000 -10,381,000                         
      net mark-to-market gains on non-trading derivative contracts
                                                               -3,573,750  -11,556,000 -2,739,000 10,485,000 -6,907,000 7,529,000 161,000 -1,242,000 -5,230,000 2,095,000                      
      realized gains and losses and other settlements
                                                                  9,924,000 -182,821,750 -732,857,000 -5,053,000 6,623,000   15,035,000                      
      less loss attributable to the noncontrolling interest
                                                                  -11,000                             
      interest expense on variable interest entity notes
                                                                   2,833,000 2,658,000 2,430,000 2,747,000 3,185,000 3,367,000 3,379,000 3,557,000     9,333,750 12,754,000 11,958,000 12,623,000 12,432,000 11,623,000 11,816,000 11,579,000         
      less net loss attributable to the noncontrolling interest
                                                                   -4,000 -14,000                           
      corporate:
                                                                                               
      less net income attributable to the noncontrolling interest
                                                                     11,000 -13,000                         
      gross premiums written
                                                                       117,743,000 118,645,000 141,280,000 159,207,000 233,766,000 286,585,000 261,139,000 249,912,000 251,903,000 212,301,000 313,458,000 219,007,000 306,022,000 237,943,000 322,628,000 229,126,000 210,587,000 363,196,000 226,434,000 280,330,000 386,005,000 197,219,000 205,110,000 195,683,000 
      ceded premiums written
                                                                       -16,553,000 4,371,000 -17,446,000 -23,534,000 -184,516,000 -35,095,000 -28,437,000 -29,484,000 -18,835,250 -26,351,000 -57,747,000 8,757,000 -37,966,000 -34,296,000 -54,038,000 26,627,000 -18,649,000 15,949,000 -33,886,000 -17,451,000 -42,313,000 -31,168,000 -26,854,000 -24,705,000 
      net premiums written
                                                                       101,190,000 123,016,000 123,834,000 135,673,000 49,250,000 251,490,000 232,702,000 220,428,000 223,748,000 185,950,000 255,711,000 227,764,000 268,056,000 203,647,000 268,590,000 255,753,000 191,938,000 379,145,000 192,548,000 262,879,000 343,692,000 166,051,000 178,256,000 170,978,000 
      realized (losses) and gains and other settlements
                                                                       -988,507,000 -837,929,000                       
      net mark-to-market losses on total return swap contracts
                                                                       -18,549,750 -28,600,000                       
      net income per diluted share
                                                                       -8.65 -8.45 2.8 -11.69 -31.81 -3.53 1.67 2.02 1.565 1.98 2.22 2.06             
      net mark-to-market gains on total return swap contracts
                                                                         -4,671,000 -40,928,000 -22,678,000 -12,856,000 -982,000 3,215,000 -4,032,000 -501,000 1,818,000 5,223,000 3,585,000 2,347,000 -5,350,000          
      other incomes
                                                                         3,297,000                      
      pre-tax incomefrom continuing operations
                                                                         1,507,385,000                      
      net mark-to-market losses on non-trading derivatives
                                                                          -1,833,000 -369,750 -1,320,000                   
      loss and loss expenses
                                                                          1,042,761,000 11,900,000 19,082,000 17,096,000 11,422,000 2,601,500 -2,543,000 12,822,000 127,000 33,563,750 89,126,000 21,657,000 23,472,000 17,700,000 17,500,000       
      interest on investment and payment agreements
                                                                          89,003,000 78,020,500 112,000,000 101,124,000 98,958,000 65,656,000 97,126,000               
      corporate
                                                                          16,076,000 2,444,250 2,857,000 3,664,000 3,256,000 9,881,000 3,036,000 4,000,000 3,643,000 3,703,000 3,548,000 5,461,000 2,282,000 2,678,000 2,601,000 2,189,000 1,938,000 2,227,000 8,273,000   
      income before income taxes
                                                                          -2,790,784,000 6,598,750 -494,895,000 232,050,000 289,240,000 231,438,250 297,149,000 326,963,000 301,641,000 184,965,000 226,978,000 260,910,000 251,972,000 246,050,000 244,458,000 231,121,000 216,381,000 219,914,000 181,449,000 177,796,000 158,942,000 
      other credit enhancement fees
                                                                           23,514,000 20,035,000 17,332,000 15,553,000 15,360,000 16,057,000 14,155,000 14,188,000 12,474,000 13,014,000 12,536,000 12,067,000 11,839,000 11,809,000 11,436,000 11,936,000 12,294,000 10,364,000 7,307,000 6,576,000 
      net premiums earned and other credit enhancement fees
                                                                           233,155,000 214,830,000 238,351,000 231,559,000 223,516,000 214,556,000 224,943,000 208,368,000 217,520,000 231,112,000 205,778,000 211,701,000 195,338,000 201,402,000 176,871,000 171,562,000 164,286,000 145,116,000 129,703,000 120,206,000 
      net mark-to-market gains on credit derivative contracts
                                                                           -5,199,021,000 -743,379,000 -56,867,000 -5,124,000 -838,000 2,572,000 5,381,000 1,953,000 18,403,000 1,555,000 -11,606,000 5,266,000 -330,000 3,256,000 6,962,000  10,002,000    
      net mark-to-market gains on non-trading derivatives
                                                                             340,000 -499,000 -309,250 -1,175,000 -306,000 244,000 12,217,250 -57,000 48,235,000          
      net realized investment losses
                                                                                         -24,000      
      income from continuing operations
                                                                                   -546,757,993.06 175,117,000 186,098,000 185,543,000 184,418,000 180,896,000 171,755,000      
      discontinued operations:
                                                                                               
      loss from discontinued operations
                                                                                       -799,000 -310,000 -240,000      
      income tax benefit
                                                                                        -124,000 -96,000      
      net loss from discontinued operations
                                                                                       -959,000 -186,000 -144,000      
      earnings per share:
                                                                                               
      earnings per diluted share:
                                                                                               
      net mark-to-market gains on derivative hedge contracts
                                                                                      691,000 22,000 41,000 63,000 11,000 51,000 677,000   
      variable interest entity
                                                                                       861,000 839,000 1,061,000      
      income tax expense
                                                                                       160,000        
      net mark-to-market losses on credit derivative contracts
                                                                                          -4,053,000  -12,176,000   
      net securities gains
                                                                                             -1,500,000 -4,510,000 
      revenue
                                                                                             13,582,000 10,966,000 
      other:
                                                                                               
      net securities losses
                                                                                             -127,000 -444,000 
      financial services
                                                                                             5,380,000 5,699,000 
    Balance Sheets:
    Quarterly
    Annual
      Unit: USD2026-03-31 2025-12-31 2025-09-30 2025-06-30 2025-03-31 2024-12-31 2024-09-30 2024-06-30 2024-03-31 2023-12-31 2023-09-30 2023-06-30 2023-03-31 2022-12-31 2022-09-30 2022-06-30 2022-03-31 2021-12-31 2021-09-30 2021-06-30 2021-03-31 2020-12-31 2020-09-30 2020-06-30 2020-03-31 2019-09-30 2019-06-30 2019-03-31 2018-12-31 2018-09-30 2018-06-30 2018-03-31 2017-09-30 2017-06-30 2017-03-31 2016-12-31 2016-09-30 2016-06-30 2016-03-31 2015-12-31 2015-09-30 2015-06-30 2015-03-31 2014-12-31 2014-09-30 2014-06-30 2014-03-31 2013-12-31 2013-09-30 2013-06-30 2013-03-31 2012-12-31 2012-09-30 2012-06-30 2012-03-31 2011-12-31 2011-09-30 2011-06-30 2011-03-31 2010-12-31 2010-09-30 2010-06-30 2010-03-31 2009-12-31 2009-09-30 2009-06-30 2009-03-31 2008-12-31 2008-09-30 2008-06-30 2008-03-31 2007-12-31 2007-09-30 2007-06-30 2007-03-31 2006-12-31 2006-09-30 2006-06-30 2006-03-31 2005-12-31 2005-09-30 2005-06-30 2005-03-31 2004-12-31 2004-09-30 2004-06-30 2004-03-31 2003-12-31 2003-09-30 2003-06-30 2003-03-31 2002-12-31 2002-09-30 2002-06-30 
                                                                                                    
        assets:
                                                                                                    
        investments:
                                                                                                    
        fixed maturity securities - available-for-sale, at fair value
      137,092,000  131,101,000 161,335,000 161,569,000  1,740,000,000 1,703,000,000 1,687,000,000  1,556,000,000 1,552,000,000 1,494,000,000  1,384,000,000 1,410,000,000 1,383,000,000                                                                              
        short-term investments, at fair value
      92,295,000 146,442,000 295,825,000 102,720,000 101,610,000 127,601,000 305,000,000 314,000,000 382,000,000 426,000,000 421,000,000 365,000,000 367,000,000 507,000,000 523,000,000 452,000,000 540,000,000 414,000,000 368,000,000 416,000,000 397,000,000 492,000,000 586,000,000 692,000,000 586,000,000 664,441,000 772,299,000 908,235,000 430,331,000 562,060,000 393,447,000 321,119,000 716,516,000 504,006,000 347,055,000 430,788,000    225,789,000 364,780,000 197,070,000 220,980,000 360,065,000 550,900,000 344,187,000 215,103,000 271,119,000,000 549,229,000 611,177,000 767,932,000 661,658,000                                           
        other investments
      24,971,000 24,971,000 28,302,000 28,193,000 28,214,000 28,294,000 561,000,000 558,000,000 558,000,000 475,000,000 461,000,000 530,000,000 557,000,000 568,000,000 559,000,000 598,000,000 660,000,000 690,000,000 663,000,000 657,000,000 600,000,000 595,000,000 502,000,000 401,000,000 363,000,000 462,427,000 469,438,000 428,556,000 391,217,000 411,604,000 394,396,000 419,896,000 439,987,000 452,032,000 478,688,000 450,307,000 419,885,000 410,727,000 320,847,000 310,600,000 314,934,000 354,784,000 332,609,000 357,016,000 290,870,000                                       808,000    1,106,000    650,000   
        total investments
      254,358,000 293,708,000 455,228,000 292,248,000 291,393,000 312,915,000 2,634,000,000 2,632,000,000 2,682,000,000 2,664,000,000 2,492,000,000 2,510,000,000 2,509,000,000 2,593,000,000 2,640,000,000 2,547,000,000 2,815,000,000 2,955,000,000 2,948,000,000 3,447,000,000 3,458,000,000 3,544,000,000 3,551,000,000 3,466,000,000 3,400,000,000 3,939,121,000 3,930,332,000 4,040,503,000 3,937,223,000 4,279,151,000 4,387,411,000 4,697,193,000 6,234,045,000 6,339,161,000 6,334,650,000 6,500,215,000 6,605,986,000 6,521,481,000 6,472,786,000 5,644,720,000 5,701,562,000 5,479,178,000 5,484,152,000 5,507,034,000 7,062,029,000 6,766,102,000 6,749,445,000 6,523,727,000,000 6,685,613,000 6,601,164,000 6,512,262,000 6,329,932,000 6,440,117,000 6,687,109,000 6,944,817,000 6,876,990,000 7,063,199,000 7,079,534,000 6,983,082,000 6,853,311,000 6,780,255,000 6,567,482,000 9,716,358,000 9,229,168,000 9,828,782,000 9,929,154,000 9,623,487,000 10,292,817,000 13,755,347,000 17,140,372,000 18,074,462,000 18,395,670,000 19,045,779,000 18,003,329,000 17,625,049,000 17,433,589,000 17,608,125,000 17,145,733,000 16,442,291,000 15,981,383,000 15,712,435,000 15,907,006,000 15,117,599,000  14,229,523,000 13,957,011,000 14,168,041,000  13,590,748,000 13,796,949,000 13,680,809,000  11,665,964,000 11,627,769,000 
        cash and cash equivalents
      93,537,000 68,440,000 51,767,000 46,383,000 51,660,000 47,275,000 70,000,000 35,000,000 44,000,000 28,000,000 46,000,000 43,000,000 48,000,000 44,000,000 29,000,000 32,000,000 60,000,000 17,000,000 14,000,000 13,000,000 23,000,000 20,000,000 37,000,000 17,000,000 58,000,000 51,951,000 17,514,000 21,840,000 63,089,000 52,505,000 44,398,000 38,485,000 107,018,000 54,238,000 118,772,000 91,025,000 21,218,000 23,044,000 29,142,000 35,744,000 27,099,000 33,965,000 26,641,000 73,903,000 43,332,000 74,461,000           21,316,000 17,379,000 7,626,000 9,497,000 69,673,000 56,677,000 114,808,000 113,230,000 149,554,000 1,130,259,000 107,866,000 107,811,000                           
        premium receivables
      87,653,000 75,085,000 74,760,000 71,875,000 64,563,000 57,222,000 342,000,000 317,000,000 299,000,000 290,000,000 278,000,000 276,000,000 272,000,000 269,000,000 268,000,000 311,000,000 317,000,000 323,000,000 327,000,000 345,000,000 356,000,000 370,000,000 372,000,000 392,000,000 403,000,000 414,744,000 441,526,000 487,397,000 495,391,000 517,197,000 553,958,000 580,707,000 601,757,000 653,176,000 652,677,000 661,337,000 706,228,000 741,414,000 782,078,000 831,575,000 895,446,000 936,924,000 951,999,000 1,000,607,000 1,266,632,000 1,356,362,000 1,418,114,000 1,453,021,000,000 1,436,010,000 1,464,898,000 1,543,098,000 1,620,621,000 1,755,830,000 1,829,874,000 1,917,536,000 2,028,479,000 2,103,193,000 1,924,925,000 2,290,920,000 2,422,596,000 2,802,811,000 2,789,353,000 2,941,546,000 3,718,158,000 4,016,775,000 4,360,680,000 4,460,670,000                            
        commission and fees receivable
      106,198,000 86,549,000 75,480,000 72,619,000 65,819,000 55,377,000                                                                                         
        reinsurance recoverable on paid and unpaid losses
      469,859,000 436,092,000 440,462,000 376,445,000 351,110,000 306,191,000 311,000,000 277,000,000 224,000,000 195,000,000 172,000,000 149,000,000 130,000,000 115,000,000 80,000,000 55,000,000 48,000,000 55,000,000 30,000,000 30,000,000 33,000,000 33,000,000 37,000,000 36,000,000 36,000,000 26,036,000 27,215,000 26,788,000 23,133,000 25,511,000 39,071,000 38,825,000 45,976,000 46,466,000 34,273,000 30,418,000 24,441,000 28,704,000 27,316,000 43,999,000 68,319,000 76,005,000 79,308,000 99,838,000 105,511,000 109,255,000 111,442,000 135,711,000,000 137,400,000 154,964,000 160,682,000 159,086,000 172,439,000 169,961,000 170,799,000 159,902,000 154,141,000 158,097,000 141,311,000 136,986,000 126,458,000 121,715,000 89,627,000 78,115,000 68,166,000 210,891,000 213,891,000 157,627,000 72,376,000 49,737,000 32,810,000 11,862,000 10,406,000 4,793,000 4,120,000 3,921,000 5,292,000 5,279,000 5,327,000 3,730,000 1,160,000 1,806,000 23,330,000  1,773,000 2,183,000 3,266,000  3,575,000 3,944,000 5,381,000    
        deferred ceded premium
      145,420,000 146,365,000 160,906,000 155,582,000 144,914,000 148,300,000 242,000,000 232,000,000 217,000,000 204,000,000 205,000,000 198,000,000 135,000,000 124,000,000 99,000,000 104,000,000 100,000,000 90,000,000 90,000,000 80,000,000 74,000,000 70,000,000 73,000,000 75,000,000 79,000,000 76,495,000 56,272,000 58,868,000 61,134,000 45,204,000 47,886,000 49,631,000 54,773,000 59,471,000 63,336,000 69,624,000 74,630,000 82,055,000 86,502,000 96,758,000 105,673,000 112,247,000 117,688,000 123,276,000 127,596,000 134,278,000 142,280,000 145,529,000,000 152,076,000 159,165,000 170,032,000 177,893,000 190,540,000 197,437,000 202,226,000 221,303,000 229,451,000 232,935,000 250,291,000 264,858,000 318,616,000 386,665,000 395,517,000 500,804,000 549,199,000 959,411,000 1,149,690,000                            
        policy acquisition costs
      16,451,000 9,732,000 9,284,000 9,407,000                                                                                           
        intangible assets, less accumulated amortization
      458,380,000 474,998,000 339,197,000 353,904,000 345,061,000 344,775,000 598,000,000 285,000,000 293,000,000 307,000,000 312,000,000                                                                                    
        goodwill
      533,497,000 540,345,000 445,382,000 451,808,000 429,314,000 418,234,000 434,000,000 70,000,000 70,000,000 70,000,000 70,000,000 61,000,000 61,000,000 61,000,000 46,000,000 46,000,000 46,000,000 46,000,000                        514,511,000 514,511,000 514,511,000 514,511,000 514,511,000 514,511,000 514,511,000,000 514,511,000 514,511,000                                             
        other assets
      101,673,000 92,003,000 95,424,000 99,698,000 107,829,000 92,317,000 228,000,000 163,000,000 129,000,000 129,000,000 94,000,000 89,000,000 85,000,000 84,000,000 85,000,000 83,000,000 94,000,000 68,000,000 114,000,000 121,000,000 115,000,000 114,000,000 60,000,000 145,000,000 144,000,000 113,189,000 190,566,000 90,977,000 112,788,000 22,191,000 33,631,000 36,332,000 48,228,000 70,025,000 77,294,000 158,423,000 239,663,000 252,163,000 221,206,000 185,877,000 199,294,000 163,075,000 221,252,000 186,985,000 173,219,000 127,898,000 72,865,000 35,927,000,000 41,349,000 33,738,000 40,365,000 39,715,000 63,759,000 103,804,000 58,875,000 104,300,000 126,672,000 127,174,000 75,959,000 82,579,000 216,644,000 173,270,000 224,776,000 229,311,000 700,497,000 433,677,000 622,645,000 759,595,000 277,298,000 178,471,000 175,562,000 100,484,000 122,544,000 120,533,000 114,393,000 107,005,000 113,619,000 105,885,000 101,649,000 160,126,000 150,132,000 139,262,000 165,091,000 26,126,000 69,577,000 76,175,000 72,467,000 24,523,000 43,978,000 46,833,000 49,115,000 15,960,000 49,290,000 648,212,000 
        total assets
      2,267,026,000 2,223,317,000 2,147,890,000 8,522,386,000 8,253,282,000 8,058,378,000 9,256,000,000 8,184,000,000 8,429,000,000 8,428,000,000 7,847,000,000 8,132,000,000 8,219,000,000 7,973,000,000 9,412,000,000 10,061,000,000 11,531,000,000 12,303,000,000 12,228,000,000 12,907,000,000 12,840,000,000 13,220,000,000 12,812,000,000 12,761,000,000 12,777,000,000 13,451,104,000 14,713,066,000 15,022,899,000 14,588,711,000 15,093,464,000 21,535,223,000 22,847,966,000 23,292,583,000 23,005,443,000 22,763,560,000 22,635,702,000 24,015,629,000 23,199,111,000 23,718,591,000 23,728,070,000 24,266,919,000 25,513,636,000 25,386,610,000 25,159,864,000 26,590,785,000 27,723,353,000 27,114,248,000 27,106,939,000,000 28,633,638,000 27,475,367,000 26,164,660,000 27,007,164,000 26,947,892,000 26,611,791,000 27,372,884,000 27,113,695,000 27,626,582,000 27,940,429,000 27,410,304,000 29,047,113,000 31,328,239,000 30,055,785,000 35,815,677,000 18,886,367,000 18,099,056,000 20,045,165,000 20,182,397,000 17,256,398,000 20,446,175,000 22,875,081,000 24,919,262,000 23,565,011,000 21,981,091,000 21,061,741,000 20,111,860,000 20,267,813,000 21,010,691,000 20,273,770,000 19,736,382,000 19,725,140,000 19,062,301,000 19,529,924,000 18,625,776,000 5,859,405,000 16,992,417,000 16,851,506,000 17,457,448,000 5,086,148,000 16,344,435,000 16,797,299,000 16,344,942,000 4,286,664,000 14,688,079,000 13,869,466,000 
        liabilities and stockholders’ equity:
                                                                                                    
        liabilities:
                                                                                                    
        unearned premiums
      198,681,000 187,178,000 197,133,000 191,060,000 181,387,000 182,446,000 458,000,000 445,000,000 429,000,000 422,000,000 407,000,000 394,000,000 389,000,000 372,000,000 359,000,000 385,000,000 393,000,000 395,000,000 402,000,000 421,000,000 438,000,000 456,000,000 468,000,000 492,000,000 507,000,000 527,771,000 556,908,000 591,397,000 629,971,000 669,820,000 721,689,000 762,240,000 817,538,000 893,456,000 924,686,000 967,258,000 1,048,754,000 1,122,946,000 1,192,796,000 1,280,282,000 1,428,230,000 1,528,269,000 1,583,615,000 1,673,785,000 1,953,392,000 2,070,312,000 2,167,764,000 2,255,680,000,000 2,303,627,000 2,372,807,000 2,623,445,000 2,778,401,000 2,985,542,000 3,138,275,000 3,291,152,000 3,457,157,000 3,520,801,000 3,408,568,000 3,821,726,000 4,007,886,000 4,442,271,000 4,714,527,000 4,926,807,000 5,687,114,000 6,100,656,000 6,594,046,000 6,929,790,000 2,382,152,000 2,547,414,000 2,786,546,000 3,059,295,000 3,123,860,000 3,128,278,000 3,061,673,000 3,045,911,000 3,037,544,000 3,030,641,000 3,042,128,000 2,966,959,000 2,954,718,000 2,875,956,000 2,892,168,000 2,788,930,000  2,731,657,000 2,727,315,000 2,576,080,000  2,470,122,000 2,371,250,000 2,163,232,000  1,926,789,000 1,869,659,000 
        loss and loss adjustment expense reserves
      487,261,000 459,990,000 437,539,000 383,969,000 373,105,000 349,062,000 938,000,000 890,000,000 851,000,000 893,000,000 850,000,000 863,000,000 851,000,000 805,000,000                                                                                 
        ceded premiums payable
      89,148,000 80,561,000 87,635,000 90,557,000 81,358,000 53,002,000 165,000,000 140,000,000 110,000,000 90,000,000 95,000,000 96,000,000 38,000,000 39,000,000 33,000,000 44,000,000 40,000,000 33,000,000 33,000,000 33,000,000 24,000,000 27,000,000 27,000,000 27,000,000 28,000,000 29,950,000 30,795,000 31,745,000 32,913,000 34,306,000 35,594,000 36,451,000 38,593,000 39,664,000 40,201,000 42,529,000 43,511,000 45,727,000 47,338,000 53,494,000 57,651,000 58,002,000 59,268,000 60,436,000 61,104,000 64,740,000 69,892,000 85,424,000,000 86,028,000 89,435,000 92,085,000 94,527,000 94,089,000 98,279,000 99,643,000 115,555,000 120,843,000 121,887,000 134,248,000 141,450,000 182,725,000 224,740,000 223,747,000 291,843,000 329,849,000 576,944,000 665,137,000                            
        deferred program fees and reinsurance commissions
      6,929,000 6,978,000 7,754,000 7,346,000 7,176,000 7,500,000 8,000,000 7,000,000 7,000,000 6,000,000 7,000,000 6,000,000 6,000,000 5,000,000                                                                                 
        commissions payable
      118,086,000 115,555,000 109,317,000 96,875,000 81,017,000 71,431,000                                                                                         
        deferred taxes
      60,553,000 65,217,000 68,865,000 72,003,000 69,742,000 70,135,000 100,000,000            28,000,000 29,000,000 20,000,000 24,000,000 28,000,000 24,000,000 26,000,000 30,150,000 31,716,000 39,201,000 40,130,000 27,537,000 32,781,000 34,804,000 1,930,000 1,866,000 1,746,000 1,720,000 1,736,000 1,712,000 1,759,000 2,205,000 1,957,000 1,955,000 1,905,000 2,079,000 2,176,000 2,314,000 2,202,000 2,199,000,000 1,611,000 1,564,000 1,540,000 1,586,000            11,250,000  105,549,000 1,145,423,000 2,127,499,000 2,905,260,000 2,191,723,000 3,560,396,000 2,116,380,000 21,319,000                      
        short-term debt
         150,000,000 150,000,000 150,000,000 148,000,000                                                                                        
        long-term debt
      117,062,000 117,558,000     518,000,000 515,000,000 512,000,000 508,000,000 505,000,000 501,000,000 497,000,000 639,000,000 2,201,000,000 2,189,000,000 2,242,000,000 2,230,000,000 2,215,000,000 2,671,000,000 2,661,000,000 2,739,000,000 2,737,000,000 2,749,000,000 2,760,000,000 2,954,929,000 2,946,620,000 2,929,227,000 2,928,929,000 2,937,771,000 2,796,389,000 2,957,732,000 988,148,000 988,150,000 1,015,526,000 1,114,405,000 1,109,814,000 1,112,920,000 1,115,284,000 1,124,950,000 1,123,003,000 977,751,000 979,001,000 971,116,000 1,219,310,000 981,424,000 972,147,000 963,178,000,000 954,721,000 945,940,000 153,873,000 150,170,000 146,909,000 144,036,000 227,189,000 223,601,000 220,440,000 217,345,000 210,837,000 208,260,000 1,823,327,000 1,815,017,000 1,633,400,000 4,640,184,000 2,751,625,000 3,640,243,000 1,823,979,000 1,868,690,000 1,895,858,000 1,892,639,000 1,891,183,000 1,669,945,000 1,669,944,000 1,664,705,000 1,389,176,000 991,804,000 2,213,303,000 2,164,061,000 2,282,187,000 2,233,582,000 1,860,727,000 1,836,277,000 1,888,886,000            
        accrued interest payable
      1,305,000 1,343,000  2,944,000 2,695,000 2,560,000 515,000,000 500,000,000 487,000,000 475,000,000 462,000,000 450,000,000 438,000,000 427,000,000 576,000,000 559,000,000 593,000,000 576,000,000 555,000,000 532,000,000 516,000,000 517,000,000 499,000,000 474,000,000 457,000,000 423,815,000 407,096,000 391,335,000 375,808,000 356,711,000 237,558,000 244,199,000 417,522,000 397,974,000 396,924,000 421,975,000 400,737,000 380,117,000 371,688,000 355,536,000 334,999,000 339,006,000 322,408,000 304,139,000 376,773,000 339,975,000 317,052,000 294,817,000,000 271,330,000 249,387,000 246,378,000 228,835,000 210,108,000 192,984,000 196,853,000 170,169,000 141,162,000 114,451,000 86,387,000 61,708,000 90,975,000 58,345,000 47,070,000 50,607,000 41,948,000 67,517,000 27,318,000 68,806,000 67,328,000 80,477,000 67,686,000 113,443,000 116,624,000 93,855,000 103,685,000 105,129,000 108,247,000 78,321,000 88,550,000 108,195,000 79,581,000 68,522,000 55,389,000 6,203,000 59,932,000 56,917,000 47,012,000 6,203,000 64,547,000 67,415,000 54,621,000 6,275,000 70,278,000 78,630,000 
        other liabilities
      158,458,000 102,771,000 92,226,000 95,900,000 91,429,000 89,036,000 262,000,000 203,000,000 259,000,000 199,000,000 168,000,000 136,000,000 141,000,000 163,000,000 244,000,000 124,000,000 135,000,000 133,000,000 108,000,000 102,000,000 123,000,000 106,000,000 91,000,000 83,000,000 131,000,000 95,267,000 137,757,000 71,402,000 62,085,000 61,533,000 58,191,000 55,209,000 65,840,000 72,582,000 67,881,000 76,589,000 52,177,000 59,040,000 68,693,000 61,134,000 59,809,000 57,653,000 56,914,000 63,396,000 66,101,000 60,086,000 58,819,000 67,377,000,000 77,270,000 86,663,000 91,057,000 102,488,000 98,161,000 94,678,000 97,144,000 107,441,000 107,242,000 101,156,000 117,398,000 124,748,000 138,301,000 140,999,000 226,236,000 248,715,000 253,670,000 313,824,000 291,443,000 279,616,000 206,590,000 204,322,000 231,105,000 270,734,000 322,449,000 317,018,000 225,090,000 275,670,000 254,577,000 243,559,000 211,199,000 253,969,000 240,928,000 204,209,000 202,556,000 27,964,000 225,158,000 233,663,000 227,659,000 24,670,000 163,184,000 148,614,000 131,086,000 29,553,000 138,175,000 595,637,000 
        total liabilities
      1,237,483,000 1,137,151,000 1,000,469,000 7,303,678,000 7,041,817,000 6,862,857,000 7,383,000,000 6,748,000,000 6,993,000,000 6,997,000,000 6,507,000,000 6,809,000,000 6,892,000,000 6,647,000,000 8,324,000,000 9,198,000,000 10,538,000,000 11,187,000,000 11,088,000,000 11,764,000,000 11,697,000,000 12,074,000,000 11,718,000,000 11,632,000,000 11,716,000,000 11,822,440,000 13,160,150,000 13,357,011,000 12,955,564,000 13,294,655,000 19,471,302,000 20,738,801,000 21,520,446,000 21,067,230,000 20,874,644,000 20,657,678,000 21,839,255,000 21,136,274,000 21,706,960,000 21,769,724,000 22,637,882,000 23,466,425,000 23,548,889,000 23,486,129,000 25,340,095,000 26,499,822,000 25,885,437,000 26,128,517,000,000 27,746,888,000 26,913,300,000 29,034,730,000 30,254,131,000 30,435,405,000 30,367,170,000 30,286,526,000 30,263,228,000 29,807,158,000 30,014,410,000 29,504,201,000 30,401,341,000 32,545,819,000 31,478,464,000 37,292,462,000 20,520,012,000 20,273,597,000 24,631,609,000 23,367,864,000 21,038,707,000 21,333,087,000 20,935,612,000 23,633,524,000 21,285,118,000 16,331,179,000 15,019,912,000 14,122,681,000 14,083,624,000 15,005,374,000 14,643,549,000 14,261,495,000 14,352,933,000 13,868,306,000 14,236,850,000 13,512,548,000 834,948,000 12,183,579,000 12,387,293,000 12,927,920,000 831,590,000 12,255,148,000 12,755,797,000 12,581,430,000 661,485,000 11,067,955,000 10,508,265,000 
        commitments and contingencies
                                                                                                    
        redeemable noncontrolling interest
      195,969,000 252,981,000 188,247,000 190,347,000 185,417,000 140,860,000 204,000,000 17,000,000 17,000,000 17,000,000 22,000,000 20,000,000 20,000,000 20,000,000 18,000,000 18,000,000 18,000,000 18,000,000 20,000,000 20,000,000 20,000,000 7,000,000                                                                         
        stockholders’ equity:
                                                                                                    
        preferred stock, par value 0.01 per share...
                                                                                                    
        common stock, par value 0.01 per share...
      489,000 489,000 489,000 489,000 489,000 489,000                    456,000 456,000 456,000 454,000 454,000 454,000 454,000 453,000 453,000 453,000 452,000 451,000 451,000 450,000 450,000 450,000 450,000 450,000 450,000 450,000 450,000 450,000     3,080,000    3,080,000        2,944,000    2,944,000    1,092,000    1,092,000    1,092,000    1,089,000    1,073,000    1,062,000   
        additional paid-in capital
      380,263,000 369,860,000 367,077,000 347,939,000 333,356,000 331,007,000 328,000,000 295,000,000 291,000,000 292,000,000 286,000,000 283,000,000 278,000,000 274,000,000 270,000,000 267,000,000 262,000,000 257,000,000 253,000,000 249,000,000 246,000,000 242,000,000 240,000,000 237,000,000 235,000,000 229,128,000 226,794,000 223,545,000 219,429,000 218,050,000 208,328,000 204,172,000 198,629,000 197,652,000 196,788,000 195,267,000 194,383,000 193,074,000 191,895,000 190,813,000 189,981,000 190,414,000 189,533,000 189,138,000 188,648,000 188,060,000 187,210,000 185,672,000,000 184,566,000 184,565,000 2,172,027,000 2,172,027,000 2,172,027,000 2,172,027,000 2,172,027,000 2,172,027,000 2,172,027,000 2,172,027,000 2,187,593,000  2,186,372,000 2,185,134,000 2,174,247,000 2,172,656,000 2,171,848,000 2,038,540,000 2,035,191,000 2,030,031,000 2,028,141,000 2,031,159,000 2,024,504,000 839,952,000 836,742,000 829,853,000 814,223,000 790,168,000 755,749,000 745,337,000 739,664,000 723,680,000 716,870,000 711,294,000 702,409,000 694,465,000 672,411,000 670,293,000 646,989,000 606,468,000 581,083,000 573,797,000 553,078,000 550,289,000 548,823,000 549,509,000 
        accumulated other comprehensive income
      1,224,000 8,483,000 11,780,000 -66,013,000 -133,168,000 -188,436,000 -81,000,000 -175,000,000 -175,000,000 -160,000,000 -262,000,000 -209,000,000 -217,000,000 -253,000,000 -315,000,000 -196,000,000 -70,000,000 58,000,000 64,000,000 87,000,000 61,000,000 79,000,000 22,000,000 -48,000,000 -149,000,000 26,407,000 19,088,000 22,542,000 -48,715,000 97,825,000 45,854,000 99,476,000 62,680,000 38,828,000 -2,775,000 -38,990,000 61,917,000 50,775,000 58,012,000 15,215,000 72,887,000 95,362,000 169,329,000 220,283,000 250,865,000 306,328,000 104,417,000 11,661,000,000 -10,246,000 -103,507,000 720,071,000 625,385,000 527,969,000 417,593,000 445,797,000 463,259,000 478,218,000 509,300,000 371,235,000  347,738,000 219,939,000        -727,721,000 -554,578,000 -22,138,000 71,300,000 69,341,000 187,605,000 197,576,000 199,752,000 42,323,000 117,205,000 202,312,000 235,502,000 338,521,000 206,212,000 296,814,000 285,192,000 120,035,000 353,500,000 266,919,000 271,493,000 378,273,000 272,776,000 265,427,000 319,793,000 158,746,000 
        retained earnings
      363,751,000 370,431,000 491,733,000 607,548,000 681,489,000 742,185,000 1,235,000,000 1,265,000,000 1,266,000,000 1,246,000,000 1,257,000,000 1,191,000,000 1,206,000,000 1,245,000,000 1,068,000,000 728,000,000 723,000,000 726,000,000 746,000,000 732,000,000 761,000,000 759,000,000 773,000,000 881,000,000 917,000,000 1,313,052,000 1,246,990,000 1,376,244,000 1,421,302,000 1,441,857,000 1,545,702,000 1,541,464,000 1,246,736,000 1,437,641,000 1,431,397,000 1,557,681,000 1,652,846,000 1,551,724,000 1,494,181,000 1,478,439,000        505,219,000,000 436,656,000 205,681,000                    1,268,866,000 449,801,000 2,107,773,000 5,387,639,000 5,773,888,000 5,626,344,000 5,454,575,000 5,265,443,000 5,083,048,000 4,864,748,000 4,692,701,000 4,520,475,000 4,368,225,000 4,203,859,000 4,032,089,000 3,860,248,000 3,698,656,000 3,534,042,000 3,380,098,000 3,235,642,000 3,088,365,000 2,946,246,000 2,820,281,000 2,772,509,000 2,652,042,000 
        treasury stock
      -33,109,000 -33,473,000 -27,695,000 -30,124,000 -29,945,000 -28,339,000 -17,000,000 -17,000,000 -17,000,000 -17,000,000 -17,000,000 -15,000,000 -14,000,000 -15,000,000 -15,000,000 -16,000,000 -2,000,000 -3,000,000 -3,000,000 -5,000,000 -5,000,000 -1,000,000 -1,000,000 -1,000,000 -2,000,000 -347,000 -380,000 -813,000 -473,000 -527,000 -527,000 -511,000 -471,000 -471,000 -1,057,000 -496,000   -12,000 -118,000 -256,000 -56,000 -56,000                                                    
        total octave specialty group, inc. stockholders’ equity
      712,618,000 715,790,000                                                                                             
        nonredeemable noncontrolling interest
      120,956,000 117,395,000 115,790,000 168,522,000 173,827,000 197,755,000 205,000,000 51,000,000 53,000,000 53,000,000 53,000,000 53,000,000 53,000,000 53,000,000 62,000,000 62,000,000 60,000,000 60,000,000 60,000,000 60,000,000 60,000,000 60,000,000                                                                         
        total stockholders’ equity
      833,574,000 833,185,000 959,174,000 1,028,361,000 1,026,048,000 1,054,661,000 1,670,000,000 1,419,000,000 1,418,000,000 1,415,000,000 1,318,000,000 1,303,000,000 1,307,000,000 1,305,000,000 1,071,000,000 846,000,000 974,000,000 1,098,000,000 1,121,000,000 1,123,000,000 1,123,000,000 1,140,000,000 1,095,000,000 1,129,000,000 1,062,000,000 1,628,664,000 1,552,916,000 1,665,888,000 1,633,147,000 1,798,809,000 2,063,921,000 2,109,165,000 1,772,137,000 1,938,213,000 1,888,916,000 1,978,024,000 2,176,374,000 2,062,837,000 2,011,631,000 1,958,346,000 1,629,037,000 2,047,211,000 1,837,721,000 1,673,735,000 1,250,690,000 1,223,531,000 1,228,811,000 978,422,000,000 886,750,000 562,067,000                  -3,782,309,000 -886,912,000 1,939,469,000 1,285,738,000 2,279,893,000 5,649,912,000 6,041,829,000 5,989,179,000 6,184,189,000 6,005,317,000 5,630,221,000 5,474,887,000 5,372,207,000 5,193,995,000 5,293,074,000 5,113,228,000 5,024,457,000 4,808,838,000 4,464,213,000 4,529,528,000 4,254,558,000 4,089,287,000 4,041,502,000 3,763,512,000 3,625,179,000 3,620,124,000 3,361,201,000 
        total liabilities, redeemable noncontrolling interest and stockholders’ equity
      2,267,026,000 2,223,317,000 2,147,890,000 8,522,386,000 8,253,282,000 8,058,378,000 9,256,000,000 8,184,000,000 8,429,000,000 8,428,000,000 7,847,000,000 8,132,000,000 8,219,000,000 7,973,000,000 9,412,000,000 10,061,000,000 11,531,000,000 12,303,000,000 12,228,000,000 12,907,000,000 12,840,000,000 13,220,000,000                                                                         
        fixed maturity securities, at fair value
       122,295,000    157,020,000 2,238,000,000 2,101,000,000 2,162,000,000 1,710,000,000 1,948,000,000 2,056,000,000 2,119,000,000 1,395,000,000 2,119,000,000 2,642,000,000 3,364,000,000 1,730,000,000 1,797,000,000 2,253,000,000 2,341,000,000 2,317,000,000                                                                         
        assets of discontinued operations
                                                                                                    
        liabilities of discontinued operations
                                                                                                    
        total ambac financial group, inc. stockholders’ equity
        843,384,000 859,839,000 852,221,000 856,906,000 1,465,000,000 1,368,000,000 1,365,000,000 1,362,000,000 1,265,000,000 1,250,000,000 1,254,000,000 1,252,000,000 1,009,000,000 784,000,000 914,000,000 1,038,000,000 1,061,000,000 1,063,000,000 1,063,000,000 1,080,000,000 1,035,000,000 1,069,000,000 1,002,000,000 1,568,696,000 1,492,948,000 1,621,974,000 1,591,997,000 1,757,659,000 1,799,811,000 1,845,055,000 1,508,027,000 1,674,103,000 1,624,806,000 1,713,914,000 1,909,597,000 1,796,024,000 1,744,526,000 1,684,799,000 1,355,008,000 1,772,866,000 1,563,257,000 1,399,105,000 975,650,000 948,075,000 953,219,000 702,983,000,000 611,426,000 287,189,000                                             
        assets held-for-sale
         6,592,417,000 6,392,004,000 6,267,200,000                                                                                         
        liabilities held-for-sale
         6,213,024,000 6,003,908,000 5,887,685,000                                                                                         
        deferred acquisition costs
          9,615,000 8,572,000 13,000,000 12,000,000 12,000,000 11,000,000 8,000,000 4,000,000 4,000,000 3,000,000                                     192,306,000 199,160,000 205,818,000 211,907,000 219,001,000 223,510,000 225,429,000 238,225,000 247,746,000 250,649,000 251,971,000 263,258,000 273,405,000 279,704,000 300,127,000 210,368,000 189,263,000 207,229,000 221,788,000 227,827,000 239,799,000 255,639,000 277,619,000 271,235,000 263,282,000 252,115,000 220,252,000 213,086,000 215,436,000 202,195,000 201,734,000 198,805,000 201,643,000  194,186,000 190,299,000 176,523,000  179,841,000 174,646,000 174,440,000  172,718,000 170,345,000 
        fixed maturity securities pledged as collateral, at fair value
            27,000,000 25,000,000 26,000,000      15,000,000 15,000,000 15,000,000 15,000,000 15,000,000 15,000,000 15,000,000 15,000,000                                                                         
        fixed maturity securities - trading, at fair value
             31,000,000 29,000,000 27,000,000 28,000,000 28,000,000 29,000,000 59,000,000 105,000,000                                                                                
        short-term investments pledged as collateral, at fair value
               27,000,000 27,000,000 36,000,000 61,000,000 64,000,000 55,000,000 70,000,000 99,000,000 105,000,000 105,000,000 105,000,000 105,000,000 125,000,000 152,000,000 155,000,000 85,000,000                                                                      
        subrogation recoverable
            124,000,000 128,000,000 130,000,000 137,000,000 179,000,000 139,000,000 146,000,000 271,000,000 1,949,000,000 1,667,000,000 1,714,000,000 2,092,000,000 2,113,000,000 2,097,000,000 2,076,000,000 2,156,000,000 2,194,000,000 2,215,000,000 2,192,000,000 2,082,268,000 1,984,826,000 1,916,117,000 1,932,960,000 1,898,611,000 1,876,188,000 1,894,778,000 703,930,000 658,875,000 679,974,000 684,731,000 703,621,000 677,157,000 660,471,000 1,229,293,000 982,202,000 981,402,000 984,129,000 953,274,000 489,237,000 484,152,000 512,235,000 498,478,000,000 484,605,000 501,087,000 545,007,000 497,346,000 514,084,000 442,097,000 519,404,000 659,810,000 714,496,000 739,658,000 796,622,000 714,270,000 1,222,216,000 1,046,610,000 877,908,000 902,612,000 570,133,000 198,431,000 197,690,000                            
        variable interest entity assets:
                                                                                                    
        restricted cash
            47,000,000 62,000,000 252,000,000 246,000,000 256,000,000 266,000,000 256,000,000 17,000,000 6,000,000 5,000,000 7,000,000 5,000,000 6,000,000 17,000,000 16,000,000 13,000,000 10,000,000 15,000,000 31,000,000 12,561,000   19,405,000 1,024,000 1,052,000 1,134,000 37,793,000 5,015,000 5,005,000 4,873,000 5,477,000 5,461,000 5,642,000 5,822,000 5,895,000 5,944,000 6,219,000 7,708,000 7,337,000 7,712,000 8,552,000 17,498,000,000 23,045,000 22,994,000 2,258,000  2,500,000 2,500,000 2,500,000 2,500,000   2,500,000 2,500,000 1,952,000 1,977,000 100,941,000                                
        loans, at fair value
            1,651,000,000 1,567,000,000 1,604,000,000 1,663,000,000 1,551,000,000 1,772,000,000 1,856,000,000 1,829,000,000 1,682,000,000 2,144,000,000 2,469,000,000 2,718,000,000 2,784,000,000 2,943,000,000 2,948,000,000 2,998,000,000 2,783,000,000 2,787,000,000 2,932,000,000 2,965,539,000 4,288,572,000 4,375,761,000 4,287,664,000 4,563,091,000 10,751,199,000 11,558,331,000 11,557,788,000 11,301,298,000 11,015,305,000 10,658,963,000 11,476,766,000 11,074,772,000 11,516,242,000 11,690,324,000 12,183,061,000 13,005,216,000 12,789,201,000 12,371,177,000 12,503,484,000 13,743,231,000 13,269,452,000                                                
        derivative and other assets
            326,000,000 303,000,000 313,000,000 318,000,000 220,000,000 226,000,000 244,000,000 241,000,000                                                                                 
        variable interest entity liabilities:
                                                                                                    
        derivative liabilities
            1,223,000,000 1,136,000,000 1,170,000,000 1,197,000,000 22,000,000 37,000,000 44,000,000 38,000,000 40,000,000 61,000,000 76,000,000 95,000,000 94,000,000 98,000,000 86,000,000 114,000,000 126,000,000 134,000,000 137,000,000 103,314,000 88,245,000 86,534,000 76,699,000 61,331,000 67,648,000 71,584,000 90,899,000 91,549,000 244,235,000 319,286,000 435,410,000 437,163,000 408,331,000 353,358,000 375,835,000 342,784,000 447,356,000 406,944,000 348,427,000 342,273,000 300,840,000 253,898,000,000 400,382,000 451,790,000 505,746,000 453,214,000 455,587,000 394,040,000 387,476,000 414,508,000 456,522,000 364,913,000 352,345,000 348,791,000 486,878,000 452,136,000 3,636,091,000 3,536,858,000 4,652,390,000 7,608,133,000 8,146,454,000 10,089,895,000 9,419,466,000 7,451,522,000 8,744,697,000 6,685,528,000 1,451,392,000 675,290,000 654,070,000 667,066,000 846,911,000 650,188,000 699,974,000 935,440,000 987,545,000 1,187,863,000 910,512,000            
        derivative assets
                15,000,000 26,000,000 31,000,000 27,000,000 28,000,000 40,000,000 55,000,000 76,000,000 78,000,000 82,000,000 74,000,000 93,000,000 95,000,000 97,000,000 88,000,000 82,162,000 72,376,000 76,400,000 59,468,000 50,262,000 56,510,000 60,196,000 77,287,000 79,047,000 74,397,000 77,742,000 103,373,000 104,353,000 97,559,000 84,995,000 91,088,000 80,661,000 113,622,000 109,017,000 91,320,000 89,680,000 81,911,000 77,711,000,000 82,962,000 91,178,000 112,811,000 48,005,000 97,464,000 132,914,000 272,658,000 175,207,000 205,215,000 248,950,000 300,849,000 290,299,000 298,757,000 504,125,000 433,688,000 605,905,000 1,187,636,000 1,550,781,000 1,847,952,000 2,187,214,000 904,151,000 918,490,000 1,265,156,000 990,534,000 1,000,569,000 939,658,000 995,236,000 1,019,339,000 1,125,519,000 878,594,000 862,674,000 1,101,948,000 1,145,224,000 1,379,604,000 1,143,185,000            
        intangible assets
                 317,000,000 321,000,000 326,000,000 318,000,000 330,000,000 350,000,000 362,000,000 364,000,000 377,000,000 391,000,000 409,000,000                          76,140,000,000 159,505,000 162,012,000       254,163,000 318,180,000                                     
        loss and loss expense reserves
                    1,009,000,000 1,019,000,000 1,067,000,000 1,570,000,000 1,565,000,000 1,641,000,000 1,662,000,000 1,759,000,000 1,801,000,000 1,814,000,000 1,797,000,000 1,522,304,000 1,494,106,000 1,694,163,000 1,826,078,000 1,868,484,000 2,057,334,000 2,139,101,000 4,704,285,000 4,582,153,000 4,510,329,000 4,380,769,000 4,207,535,000 4,327,938,000 4,303,547,000 4,088,106,000 4,237,515,000 4,367,414,000 4,475,991,000 4,752,007,000 6,003,474,000 6,072,323,000                                       229,586,000 238,091,000         
        fixed maturity securities - trading
                     2,000,000 119,000,000                                                                              
        current taxes
                        2,000,000 3,000,000 2,000,000  2,000,000 18,000,000 16,000,000 19,663,000 14,092,000 42,830,000 47,040,000 32,509,000 34,619,000 20,180,000 18,484,000 26,082,000 25,936,000 14,280,000 16,750,000 4,858,000 3,372,000 5,835,000 985,000 1,670,000 2,333,000 5,701,000 785,000 1,488,000 3,761,000 738,000,000 3,589,000 4,224,000 97,274,000 96,778,000 97,379,000 96,752,000 97,449,000 95,709,000 98,532,000 23,435,000 24,884,000     421,438,000 50,567,000   192,669,000                           
        fixed income securities, at fair value
                            2,311,000,000 2,218,000,000 2,367,000,000 2,727,305,000 2,604,177,000 2,619,811,000 3,115,675,000 3,221,301,000 3,514,927,000 3,871,938,000 4,978,118,000 5,318,195,000 5,443,999,000 5,554,215,000 2,828,685,000 2,577,293,000 2,622,724,000 5,043,776,000 4,956,876,000 4,892,421,000 4,865,750,000 4,725,686,000 6,156,228,000 6,100,431,000 6,168,689,000 5,885,316,000,000 5,758,665,000 5,585,275,000 5,402,290,000 5,402,395,000 5,440,690,000 5,390,290,000 5,763,133,000 5,830,289,000 5,976,941,000 5,872,977,000 6,083,472,000 6,020,895,000 5,968,020,000 5,925,170,000 7,009,095,000 8,098,517,000 8,233,730,000 8,685,953,000 8,357,554,000 8,537,676,000 12,407,606,000 15,519,216,000 16,507,745,000 17,127,485,000 17,984,060,000 17,385,817,000 16,888,069,000 16,800,338,000 16,855,600,000 16,517,931,000 15,811,299,000 15,124,016,000 15,155,998,000 15,260,922,000 14,336,984,000  13,530,312,000 13,057,681,000 13,240,910,000 17,152,000 12,827,430,000 12,885,401,000 12,829,600,000 17,597,000 10,710,694,000 10,456,533,000 
        insurance intangible asset
                            383,000,000 392,000,000 406,000,000 433,524,000 454,830,000 689,255,000 718,931,000 755,734,000 786,208,000 833,040,000 877,972,000 912,173,000 931,159,000 962,080,000 1,022,865,000 1,075,605,000 1,149,966,000 1,212,112,000 1,279,448,000 1,339,427,000 1,347,295,000 1,410,920,000 1,475,012,000 1,549,384,000 1,570,070,000 1,597,965,000,000 1,620,952,000 1,621,612,000                                             
        noncontrolling interest
                            60,000,000 60,000,000 60,000,000 59,968,000 59,968,000 43,914,000 41,150,000 41,150,000 264,110,000 264,110,000 264,110,000 264,110,000 264,110,000 264,110,000 266,777,000 266,813,000 267,105,000 273,547,000 274,029,000 274,345,000 274,464,000 274,630,000 275,040,000 275,456,000 275,592,000 275,439,000,000 275,324,000 274,878,000 660,472,000 660,560,000 661,006,000 661,060,000 663,475,000 663,442,000 654,226,000 654,232,000 654,385,000  654,531,000 654,426,000 654,060,000 654,140,000 653,903,000 792,688,000 792,644,000                            
        total liabilities and stockholders’ equity
                            12,812,000,000 12,761,000,000 12,777,000,000 13,451,104,000 14,713,066,000 15,022,899,000 14,588,711,000 15,093,464,000 21,535,223,000 22,847,966,000 23,292,583,000 23,005,443,000 22,763,560,000 22,635,702,000 24,015,629,000 23,199,111,000 23,718,591,000 23,728,070,000 24,266,919,000 25,513,636,000 25,386,610,000 25,159,864,000 26,590,785,000 27,723,353,000 27,114,248,000 27,106,939,000,000 28,633,638,000 27,475,367,000                  17,256,398,000 20,446,175,000 22,875,081,000 24,919,262,000 23,565,011,000 21,981,091,000 21,061,741,000 20,111,860,000 20,267,813,000 21,010,691,000 20,273,770,000 19,736,382,000 19,725,140,000 19,062,301,000 19,529,924,000 18,625,776,000 5,859,405,000 16,992,417,000 16,851,506,000 17,457,448,000 5,086,148,000 16,344,435,000 16,797,299,000 16,344,942,000 4,286,664,000 14,688,079,000 13,869,466,000 
        fixed income securities pledged as collateral, at fair value
                               84,948,000 84,418,000 83,901,000  84,186,000 84,641,000 84,240,000 99,424,000 64,928,000 64,908,000 64,905,000    64,555,000 64,972,000 34,903,000 64,813,000 64,267,000 64,031,000 65,029,000 125,123,000 126,223,000,000 140,273,000 164,295,000 228,228,000 265,779,000 285,860,000 286,660,000 287,762,000 263,530,000 262,032,000 140,104,000 107,084,000 123,519,000 194,387,000 127,432,000 103,400,000 167,366,000 248,829,000 180,375,000 246,475,000 286,853,000  116,503,000  374,840,000 360,799,000 285,605,000 452,324,000 307,101,000 375,288,000 371,702,000 412,659,000 371,160,000 376,928,000 409,004,000 348,296,000  518,053,000 656,938,000 696,089,000  594,499,000 518,606,000 633,073,000  815,742,000 948,177,000 
        receivable for securities
                                  3,351,000 46,376,000 82,513,000 2,376,000 68,686,000 3,218,000 2,815,000 2,090,000 98,406,000 2,400,000 10,196,000 44,030,000 9,749,000 2,890,000 8,779,000 23,660,000 33,836,000 31,107,000 36,447,000 14,450,000,000 19,339,000 2,221,000 40,822,000 761,000 10,005,000 112,013,000 108,185,000 38,164,000                          49,491,000 79,898,000            
        investment income due and accrued
                                  11,576,000 10,709,000 12,157,000 20,457,000 20,137,000 24,258,000 27,288,000 26,023,000 25,456,000 25,082,000 25,386,000 25,264,000 25,113,000 25,279,000 24,994,000 25,015,000 32,818,000 34,518,000 34,641,000 37,663,000,000 34,115,000 35,718,000 33,944,000 39,742,000 37,182,000 42,651,000 39,831,000 45,328,000 41,008,000 45,562,000 39,715,000 45,066,000 37,346,000 47,995,000 46,575,000 77,195,000 66,899,000 81,840,000 76,248,000 116,769,000 139,967,000 174,382,000 145,969,000 202,737,000 175,215,000 183,207,000 154,614,000 193,199,000 182,942,000 182,352,000 150,362,000 178,779,000 155,715,000 159,483,000 138,931,000  143,930,000 142,361,000 125,957,000  140,456,000 141,911,000 121,911,000  127,961,000 156,133,000 
        loans
                                  9,913,000 10,082,000 10,007,000 10,643,000 10,390,000 10,125,000 4,237,000 4,160,000 4,513,000 4,615,000 5,109,000 5,206,000 5,499,000 5,674,000 5,494,000 5,714,000 6,057,000 6,349,000 6,250,000 6,179,000,000 6,148,000 7,053,000 8,691,000 9,203,000 10,380,000 10,153,000 19,243,000 18,996,000 20,035,000 20,271,000 20,397,000 20,167,000 20,999,000 70,849,000 71,090,000 2,716,371,000 607,949,000 581,463,000 333,051,000 798,848,000 830,985,000 827,054,000 830,063,000 867,676,000 870,637,000 861,364,000 602,624,000 625,422,000 1,199,287,000 1,196,678,000 1,321,016,000 1,344,140,000 1,347,136,000 1,352,328,000 1,365,827,000  676,690,000 835,429,000 832,959,000  837,226,000 820,447,000 838,609,000  848,399,000 932,213,000 
        payable for securities purchased
                                  1,707,000 31,292,000 16,556,000 8,849,000 55,486,000 6,126,000 15,983,000 1,084,000 201,980,000 54,696,000 16,760,000 84,690,000 87,697,000 5,494,000 34,559,000 762,000 27,263,000 15,358,000 79,697,000 4,654,000,000 82,144,000 42,901,000 17,051,000 25,000 15,009,000 5,328,000 37,856,000 1,665,000 7,481,000 17,849,000 76,361,000  2,486,000 24,151,000 399,959,000 2,074,000 22,560,000 7,746,000 3,471,000 10,256,000 7,969,000 3,054,000 91,825,000 645,000 30,852,000 168,850,000 44,266,000 95,973,000 6,588,000 144,745,000 169,996,000 11,641,000 143,379,000 130,690,000 157,560,000  79,890,000 265,126,000 158,659,000  379,584,000 447,625,000 140,321,000  241,036,000 158,027,000 
        long-term debt, at fair value
                                  5,268,596,000 5,585,860,000 11,454,746,000 12,270,124,000 12,229,569,000 11,902,682,000 11,564,054,000 11,155,936,000 11,930,434,000 11,444,892,000 11,998,561,000 12,327,960,000 12,791,012,000 13,595,792,000 13,341,902,000 12,882,076,000 13,159,174,000 14,450,434,000 13,878,577,000                                                
        obligations under investment agreements
                                         82,358,000 82,358,000 82,358,000 100,358,000 100,358,000 100,358,000 112,215,000 111,967,000 160,079,000 160,515,000 169,582,000 359,993,000 359,070,000,000 359,484,000 358,610,000 357,371,000 356,091,000 397,570,000 424,840,000 523,831,000 523,046,000 556,204,000 556,458,000                                     
        fixed income securities, available for sale, at fair value
                                          5,990,397,000 5,709,464,000 5,650,261,000                                                        
        fixed income securities pledged as collateral, available for sale, at fair value
                                          64,972,000 65,068,000 64,918,000                                                        
        short-term investments, available for sale, at fair value
                                          130,732,000 336,222,000 436,760,000                                                        
        accumulated earnings
                                              1,091,946,000 1,486,696,000 1,204,001,000 989,290,000 535,706,000 453,256,000 661,161,000                                                
        common stock held in treasury at cost, 2,459 shares at december 31, 2014 and 937 shares at december 31, 2013
                                                 -56,000                                                   
        common stock held in treasury at cost, 937 shares at september 30, 2014 and december 31, 2013
                                                  -19,000                                                  
        other investments, at fair value
                                                   256,455,000 240,530,000 241,069,000,000 237,446,000 240,417,000 113,812,000                                            
        common stock held in treasury at cost, 937 shares at june 30, 2014 and december 31, 2013
                                                   -19,000                                                 
        cash
                                                    31,700,000 77,370,000,000 28,551,000 20,515,000 53,135,000 43,837,000 90,065,000 49,012,000 39,931,000 15,999,000             92,380,000 105,596,000 99,229,000 123,933,000 26,814,000 35,729,000 31,489,000 31,868,000 42,182,000 32,795,000 26,497,000 28,295,000 28,468,000 36,560,000 41,699,000 456,000 25,838,000 33,164,000 20,046,000 323,000 37,001,000 26,980,000 51,056,000 211,000 32,342,000 27,713,000 
        losses and loss expense reserve
                                                    5,826,168,000 5,968,712,000,000 5,884,660,000 6,042,649,000 6,590,216,000 6,619,486,000 7,034,224,000 7,607,663,000 6,924,346,000 7,044,070,000 6,359,409,000 6,444,519,000 6,296,761,000 5,288,655,000 5,510,541,000 5,221,886,000 4,680,633,000 4,771,684,000 4,521,807,000 4,115,037,000 3,268,218,000 2,265,860,000 1,556,715,000 1,120,812,000  484,276,000    220,074,000    304,139,000       230,810,000        
        common stock held in treasury at cost, 937 shares at march 31, 2014 and december 31, 2013
                                                    -19,000                                                
        liabilities and stockholders’ equity
                                                                                                    
        liabilities subject to compromise
                                                        1,704,641,000 1,704,904,000 1,707,408,000 1,707,411,000 1,707,417,000 1,707,421,000 1,707,488,000 1,706,518,000 1,708,486,000 1,695,231,000                                   
        obligations under investment repurchase agreements
                                                      1,370,000 5,926,000 5,926,000 5,926,000 18,276,000 18,276,000 23,500,000 23,500,000 34,040,000 34,040,000 35,720,000 37,650,000 101,807,000 113,296,000 113,296,000 113,527,000 113,527,000 113,496,000 113,496,000 113,737,000 135,305,000 135,273,000 135,273,000 135,524,000 135,524,000 135,465,000 151,797,000 154,287,000 157,151,000 166,227,000 173,800,000 196,568,000 201,680,000 229,466,000 246,560,000  295,816,000 342,801,000 474,951,000  606,110,000 715,405,000 792,590,000  1,085,946,000 1,190,564,000 
        stockholders’ equity
                                                                                                    
        successor preferred stock, par value 0.01 per share...
                                                                                                    
        predecessor preferred stock, par value 0.01 per share...
                                                                                                    
        successor common stock, par value 0.01 per share...
                                                     450,000,000 450,000 450,000                                             
        predecessor common stock, par value 0.01 per share...
                                                                                                    
        successor common stock held in treasury at cost, 937 shares at december 31, 2013
                                                     -19,000,000                                               
        predecessor common stock held in treasury at cost, 5,580,657 shares at december 31, 2012
                                                                                                    
        stockholders’ deficit:
                                                                                                    
        preferred stock
                                                                                                    
        common stock
                                                        3,080,000  3,080,000 3,080,000 3,080,000  3,080,000 3,080,000 3,080,000  3,080,000 3,080,000 2,944,000  2,944,000 2,944,000 2,944,000  2,944,000 2,944,000 2,944,000  1,092,000 1,092,000 1,092,000  1,092,000 1,092,000 1,092,000  1,091,000 1,091,000 1,089,000  1,088,000 1,088,000 1,084,000  1,069,000 1,067,000 1,064,000  1,062,000 1,062,000 
        accumulated deficit
                                                        -6,015,025,000 -6,297,264,000 -6,440,840,000 -6,598,384,000 -5,786,940,000 -6,039,922,000 -5,076,708,000 -5,001,201,000 -4,898,771,000  -3,978,701,000 -4,031,055,000 -3,972,754,000 -3,878,015,000                               
        common stock held in treasury at cost
                                                        -410,695,000  -410,755,000 -410,755,000 -411,081,000  -411,419,000 -411,419,000 -411,419,000  -430,600,000 -454,203,000 -454,942,000  -561,495,000 -565,904,000 -582,829,000  -595,414,000 -635,779,000 -636,933,000  -646,861,000 -632,345,000 -640,085,000  -216,719,000 -241,579,000 -247,822,000  -279,943,000 -126,057,000 -341,000  -10,101,000 -25,859,000 -6,087,000    -9,652,000  -22,063,000 -158,000 
        total ambac financial group, inc. stockholders’ deficit
                                                        -3,530,542,000 -3,907,527,000 -4,148,519,000 -4,416,439,000 -3,577,117,000 -3,812,975,000 -2,834,802,000 -2,728,213,000 -2,748,282,000  -1,872,111,000 -2,077,105,000 -2,130,845,000 -2,287,785,000 -2,828,444,000 -5,379,132,000 -3,978,111,000                            
        total stockholders’ deficit
                                                        -2,870,070,000 -3,246,967,000 -3,487,513,000 -3,755,379,000 -2,913,642,000 -3,149,533,000 -2,180,576,000 -2,073,981,000 -2,093,897,000  -1,217,580,000 -1,422,679,000 -1,476,785,000 -1,633,645,000 -2,174,541,000 -4,586,444,000 -3,185,467,000                            
        total liabilities and stockholders’ deficit
                                                        26,164,660,000 27,007,164,000 26,947,892,000 26,611,791,000 27,372,884,000 27,113,695,000 27,626,582,000 27,940,429,000 27,410,304,000  31,328,239,000 30,055,785,000 35,815,677,000 18,886,367,000 18,099,056,000 20,045,165,000 20,182,397,000                            
        other
                                                         100,000 100,000 100,000 100,000 100,000    100,000 100,000 100,000 1,278,000 1,278,000 1,278,000 754,000 3,368,000 14,059,000 13,475,000 13,936,000 13,824,000 14,278,000 14,787,000 39,928,000 14,460,000 14,391,000 99,474,000 14,302,000 14,442,000  4,412,000 4,198,000 4,110,000  4,453,000 4,208,000 4,591,000    3,225,000  2,159,000 2,633,000 
        common stock held in treasury at cost, 5,580,657 shares at december 31, 2012 and 5,587,953 shares at december 31, 2011
                                                         -410,755,000                                           
        short-term investments
                                                          713,467,000 1,010,059,000 893,822,000 783,071,000 824,126,000 1,066,353,000      962,007,000    1,454,229,000 1,334,266,000 1,490,717,000 1,552,893,000 879,067,000                       
        common stock held in treasury at cost, 5,587,953 shares at december 31, 2011 and 5,893,054 shares at december 31, 2010
                                                             -411,419,000                                       
        other, at cost
                                                              100,000 100,000 100,000                                    
        restricted cash and cash equivalents
                                                              2,500,000 2,500,000                                     
        receivable for securities sold
                                                              36,085,000 34,218,000 77,449,000 23,505,000 22,578,000 14,481,000 41,995,000 3,106,000 53,339,000 102,166,000 22,877,000 15,483,000 165,626,000 29,171,000 20,111,000 11,068,000 97,816,000 48,979,000 1,743,000 12,857,000 1,909,000 2,578,000 23,295,000 2,161,000 1,136,000     152,192,000 17,823,000  96,925,000 67,000 16,478,000  508,156,000 8,649,000 
        liabilities and stockholders’ deficit:
                                                                                                    
        ambac financial group, inc.:
                                                                                                    
        short-term investments, at cost
                                                                792,426,000       1,062,072,000 1,016,090,000      686,133,000 291,979,000 270,196,000 311,759,000 277,763,000 241,798,000 203,891,000 472,034,000 175,097,000 232,882,000 428,209,000 36,994,000 176,705,000 238,184,000 226,451,000 36,327,000 164,852,000 389,145,000 214,911,000 39,863,000 137,369,000 220,426,000 
        obligations under investment and payment agreements
                                                                681,396,000 767,982,000 814,389,000 879,381,000 1,150,220,000 1,177,406,000 1,416,142,000 1,594,623,000 2,098,558,000 3,244,098,000 5,482,983,000 7,246,205,000 7,709,892,000 8,570,902,000 9,135,270,000 8,395,689,000 7,747,778,000 8,202,590,000 7,743,869,000 7,585,058,000 7,026,570,000 7,056,222,000 6,902,790,000 7,093,061,000 6,733,883,000  6,313,378,000 6,388,408,000 6,612,176,000  6,369,755,000 6,591,813,000 6,655,698,000  5,246,902,000 5,220,984,000 
        short-term investments at cost
                                                                 708,797,000                                   
        short-term investments,
                                                                  617,748,000 514,780,000 2,602,585,000  1,344,945,000                              
        liabilities and stockholders’ deficit
                                                                                                    
        stockholders’ (deficit) equity:
                                                                                                    
        accumulated other comprehensive loss
                                                                    119,660,000 -24,827,000    -1,670,198,000                           
        common stock held in treasury at cost, 6,780,093 shares at december 31, 2009 and 7,138,800 shares at december 31, 2008
                                                                     -560,543,000                               
        current income taxes
                                                                       190,495,000 191,644,000  753,832,000 627,792,000 174,044,000 97,826,000 32,312,000 49,227,000 119,258,000 49,920,000 29,281,000 87,694,000 82,704,000 16,726,000 1,627,000 11,939,000 66,242,000  33,917,000 39,385,000 52,769,000  40,663,000 25,472,000 61,541,000  36,675,000 18,750,000 
        stockholders’(deficit) equity:
                                                                                                    
        accumulated other comprehensive gains
                                                                      6,372,000                              
        retained deficit
                                                                      -4,448,113,000 -6,630,047,000 -4,341,164,000                            
        accumulated other comprehensive losses
                                                                       -224,665,000 -1,092,253,000                            
        prepaid reinsurance
                                                                         292,837,000 327,165,000 404,466,000 475,705,000 489,028,000 332,373,000 322,914,000 319,310,000 315,498,000 311,564,000 310,790,000 281,835,000 303,383,000 287,161,000 280,579,000 251,573,000  286,201,000 290,234,000 328,254,000  310,418,000 314,866,000 299,400,000  273,931,000 272,946,000 
        ceded reinsurance balances payable
                                                                         15,597,000 13,459,000 14,623,000 16,205,000 32,435,000 24,406,000 19,198,000 20,888,000 20,084,000 16,964,000 38,080,000 15,737,000 23,746,000 19,072,000 31,496,000 13,693,000  4,325,000 23,134,000 17,043,000  8,989,000 15,034,000 11,572,000  11,248,000 9,831,000 
        securities sold under agreement to repurchase
                                                                           139,000  100,000,000   128,000,000  57,000,000 20,000,000 39,000,000   42,000,000   159,200,000 223,200,000 163,200,000  144,600,000 140,390,000 278,390,000  460,495,000 409,000,000 
        minority interest
                                                                         700,000,000                           
        retained (deficit) earnings
                                                                         -3,550,768,000 -1,205,956,000                          
        common stock held in treasury at cost, 7,138,800 shares at december 31, 2008 and 7,643,073 shares at december 31, 2007
                                                                         -594,318,000                           
        accumulated other comprehensive (losses) income
                                                                          -1,116,627,000                          
        assets
                                                                                                    
        loss and loss expense reserve
                                                                            1,512,319,000  284,128,000 255,825,000 231,314,000  279,614,000 291,026,000 298,160,000  288,822,000 213,542,000 259,808,000            
        securities purchased under agreements to resell
                                                                               270,000,000  273,000,000 200,000,000 200,000,000 306,000,000 419,000,000 32,000,000 25,000,000 97,000,000  62,000,000 43,000,000 147,000,000  105,705,000 179,608,000 7,002,000  24,504,000 14,005,000 
        deferred income taxes
                                                                               183,117,000 261,448,000 263,483,000 261,228,000 132,462,000 206,659,000 257,987,000 266,199,000 295,617,000 188,529,000  192,482,000 110,304,000 229,281,000  189,079,000 248,420,000 189,108,000  270,930,000 183,214,000 
        common stock held in treasury at cost, 7,643,073 shares at december 31, 2007 and 3,462,543 shares at december 31, 2006
                                                                             -646,786,000                       
        common stock held in treasury at cost, 3,462,543 at december 31, 2006 and 3,553,650 shares at december 31, 2005
                                                                                 -259,222,000                   
        other,
                                                                                     14,173,000               
        common stock held in treasury at cost, 3,553,650 at december 31, 2005 and 0 shares at december 31, 2004
                                                                                     -247,578,000               
        investments in subsidiaries
                                                                                         5,746,384,000    4,972,186,000    4,185,367,000   
        current income taxes receivable
                                                                                         33,956,000    9,961,000    6,332,000   
        deferred income taxes receivable
                                                                                         14,681,000    24,570,000    20,684,000   
        debentures
                                                                                         791,839,000 791,823,000 791,807,000 791,791,000 791,775,000 791,759,000 791,748,000 991,731,000 616,715,000 612,717,000 612,472,000 
        note payable to subsidiary
                                                                                         8,942,000    8,942,000    8,942,000   
        common stock held in treasury at cost, 0 shares at december 31, 2004 and at december 31, 2003
                                                                                                    
        receivable for securities and loans sold
                                                                                          173,973,000          
        derivative product assets
                                                                                          1,128,726,000 978,679,000 1,394,449,000  998,562,000 1,210,181,000 1,080,086,000  961,250,000  
        liabilities and stockholders' equity
                                                                                                    
        variable interest entity floating rate notes
                                                                                          134,098,000          
        derivative product liabilities
                                                                                          932,317,000 796,363,000 1,175,826,000  839,304,000 1,010,839,000 933,752,000    
        stockholders' equity:
                                                                                                    
        variable interest entity
                                                                                           150,779,000 170,663,000        
        common stock held in treasury at cost, 0 shares at december 31, 2003 and 220,876 at december 31, 2002
                                                                                                    
        other, at fair value
                                                                                              3,967,000 3,797,000     
        receivable for investment agreements
                                                                                               80,867,000 20,655,000  21,369,000 169,000 
        losses and loss adjustment expense reserve
                                                                                              187,452,000 181,772,000 177,788,000  167,045,000 161,497,000 
        common stock held in treasury at cost, 220,876 shares at december 31, 2002 and 436,488 at december 31, 2001
                                                                                                 -11,880,000   
        reinsurance recoverable
                                                                                                  2,195,000 1,894,000 
        cash pledged as collateral
                                                                                                   9,418,000 
      Cashflow Statements:
      Quarterly
      Annual
        Unit: USD2026-03-31 2025-12-31 2025-09-30 2025-06-30 2025-03-31 2024-12-31 2024-09-30 2024-06-30 2024-03-31 2023-12-31 2023-09-30 2023-06-30 2023-03-31 2022-12-31 2022-09-30 2022-06-30 2022-03-31 2021-12-31 2021-09-30 2021-06-30 2021-03-31 2020-12-31 2020-09-30 2020-06-30 2020-03-31 2019-09-30 2019-06-30 2019-03-31 2018-12-31 2018-09-30 2018-06-30 2018-03-31 2017-09-30 2017-06-30 2017-03-31 2016-12-31 2016-09-30 2016-06-30 2016-03-31 2015-09-30 2015-03-31 2014-03-31 2013-05-01 2013-03-31 2012-12-31 2012-09-30 2012-06-30 2012-03-31 2011-12-31 2011-09-30 2011-06-30 2011-03-31 2010-12-31 2010-09-30 2010-06-30 2010-03-31 2009-12-31 2009-09-30 2009-06-30 2009-03-31 2008-12-31 2008-09-30 2008-06-30 2008-03-31 2007-12-31 2007-09-30 2007-06-30 2007-03-31 2006-12-31 2006-09-30 2006-06-30 2006-03-31 2005-12-31 2005-09-30 2005-06-30 2005-03-31 2004-12-31 2004-06-30 2004-03-31 2003-12-31 2003-06-30 2003-03-31 2002-09-30 2002-06-30 
                                                                                            
          cash flows from operating activities:
                                                                                            
          net income
        -2,863,000 -29,673,000 -111,728,000 -72,953,000 -44,737,000 -547,088,000 -29,000,000 -1,000,000 21,000,000 -16,000,000 67,000,000 -13,000,000 -33,000,000 174,000,000 340,000,000 6,000,000 2,000,000 -22,000,000 17,000,000 -28,000,000 17,000,000 -14,000,000 -108,000,000 -35,000,000 -280,000,000 66,116,000 -128,429,000 -43,201,000 -20,459,000    -190,905,000 7,110,000 -125,441,000 -94,891,000 101,438,000 58,355,000 9,415,000 -391,031,000 214,871,000 156,049,000 -76,970,000 282,252,000 143,301,000 157,373,000 -813,350,000 253,322,000       -57,574,000 -690,062,000     -2,340,817,000 -2,431,222,000 823,134,000 -1,660,343,000 -3,273,924,000 -360,613,000 173,037,000 213,343,000 202,678,000 213,523,000 238,570,000 221,140,000 204,252,000 175,117,000 186,098,000 185,543,000 188,771,000 352,321,000 171,611,000 158,752,000 300,494,000 137,923,000 368,404,000 236,713,000 
          net income from discontinued operations
         -80,890,000 -52,151,000 -30,247,000                                                                                
          net income from continuing operations
        -2,863,000 -29,673,000 -30,838,000 -20,802,000 -14,490,000                                                                                
          adjustments to reconcile net income to net cash from operating activities:
                                                                                            
          intangible amortization and depreciation
        12,214,000 13,289,000 9,746,000 9,741,000 9,176,000                                                                                
          share-based compensation
        4,722,000 2,783,000 -10,008,000 14,583,000 2,349,000 3,356,000 4,000,000   5,000,000 4,000,000 5,000,000 3,000,000 4,000,000 3,000,000 5,000,000 5,000,000 4,000,000 4,000,000 2,000,000 4,000,000 3,000,000 2,000,000 3,000,000 3,000,000 2,334,000 3,249,000 4,116,000 1,379,000 1,710,000 4,153,000 4,612,000 977,000 864,000 1,521,000 1,025,000 1,451,000 1,695,000 1,082,000 876,000 393,000 1,537,000       -15,567,000 108,000 1,114,000 1,238,000 1,421,000 1,591,000 763,000 4,805,000 3,350,000 5,160,000 -29,000 7,970,000 8,245,000 1,228,000 5,019,000 8,222,000 12,212,000 11,886,000 18,262,000 5,466,000 5,066,000 8,405,000             
          deferred income taxes
        -4,664,000                 1,000,000 -1,000,000 9,000,000 -3,000,000 -4,000,000 3,000,000 -2,000,000 -6,000,000 -2,483,000 126,000 -935,000 12,693,000 -5,241,000 -2,025,000 1,145,000 64,000 120,000 26,000 -16,000 24,000 -47,000 -446,000 2,000 -174,000 3,000 30,000 -46,000             1,000 572,711,000 670,875,000 1,076,774,000 -504,164,000 1,461,910,000 -1,212,234,000 -2,010,342,000 -184,343,000 -11,354,000 3,233,000 -2,872,000 38,049,000 -30,287,000 165,000 7,826,000 29,811,000 18,984,000 14,654,000  18,865,000 6,676,000  -1,767,000 -1,146,000 2,186,000 4,503,000 
          unearned premiums
        12,448,000 4,586,000 749,000 -995,000 2,327,000 -8,324,000 3,000,000 1,000,000 -6,000,000 16,000,000 5,000,000 -57,000,000 6,000,000 -11,000,000 -22,000,000 -14,000,000 -11,000,000 -7,000,000 -30,000,000 -23,000,000 -22,000,000 -8,000,000 -21,000,000 -12,000,000 -7,000,000 -49,813,000 -31,933,000 -36,289,000 -55,428,000 -49,804,000 -38,981,000 -18,329,000 -73,307,000 -27,548,000 -36,272,000 -78,418,000 -94,962,000 -38,530,000 -77,230,000 -93,465,000 -84,582,000 -84,667,000 44,635,000 -147,095,000 -194,494,000 -145,836,000 -148,088,000 -146,928,000 -55,496,000 115,717,000 -395,802,000 -171,593,000 -380,627,000 -204,207,000 -203,428,000 -655,020,000 -365,147,000 -83,178,000 -145,465,000 -208,110,000 -130,934,000 -161,831,000 -201,510,000 -51,242,000 -161,073,000 57,146,000 12,158,000 4,555,000 16,699,000 -12,261,000 46,214,000 33,789,000 62,540,000 -22,794,000 74,232,000 55,794,000  217,052,000 27,797,000  223,663,000 31,111,000 140,241,000 84,096,000 
          losses and loss expenses
        -6,496,000 26,821,000 -10,445,000 -14,473,000 -20,876,000 7,779,000 18,000,000 -11,000,000 -4,000,000 64,000,000 -78,000,000 1,000,000 143,000,000 1,548,000,000 -315,000,000 -7,000,000 -6,000,000 1,000,000 -92,000,000 -39,000,000 -17,000,000 -2,000,000 7,000,000 -6,000,000 77,000,000 -72,271,000 -269,513,000 -118,801,000 -74,164,000 -123,997,000 -63,202,000 -1,371,840,000 75,624,000 75,505,000 131,188,000 187,782,000 -191,409,000 56,659,000 800,946,000 -123,013,000 -197,332,000 -146,494,000 43,764,000 -78,527,000 -384,647,000 -647,904,000 761,462,000 9,785,000         -92,551,000 177,793,000 897,008,000 408,308,000 623,894,000 413,264,000                 41,160,000      
          ceded premiums payable
        8,587,000 -7,074,000 -2,922,000 9,199,000 28,356,000 -51,663,000 25,000,000 30,000,000 20,000,000 -4,000,000 -1,000,000 58,000,000 -1,000,000   4,000,000 7,000,000 -1,000,000 9,000,000 -2,000,000 -1,000,000 -1,000,000 -1,000,000 -845,000 -950,000 -1,168,000 -1,393,000 -1,288,000 -857,000 -1,425,000 -1,071,000 -537,000 -2,328,000 -982,000 -2,216,000 -1,611,000 -6,156,000 -351,000 -1,168,000 -1,070,000 -591,000 -2,442,000 438,000 -4,190,000 -1,364,000 -15,912,000 -5,288,000 -1,044,000 -12,361,000 -7,202,000 -41,275,000 -42,015,000 993,000 -68,096,000  -247,095,000 -88,193,000 -14,247,000                         
          premium and commissions receivables
        -32,204,000 -11,617,000                                                                                   
          commissions payable
        2,531,000 -7,143,000                                                                                   
          corporate costs reallocated to continuing operations
         1,521,000 2,502,000 2,763,000                                                                                
          other
        -4,354,000 7,362,000 -31,240,000 15,876,000 -3,341,000 46,237,000 -22,000,000 -1,000,000 -23,000,000 27,000,000 7,000,000 4,000,000 -25,000,000 -235,000,000 2,000,000 33,000,000 48,000,000 -7,000,000 5,000,000 -23,000,000 -10,000,000 -13,000,000 9,000,000 63,000,000 -8,076,000 38,912,000 56,579,000 6,471,000 9,376,000 11,867,000 34,299,000 -5,989,000 14,217,000 1,704,000 -41,913,000 58,742,000 -42,952,000 -9,398,000 102,987,000 58,229,000 52,397,000 -115,816,000 49,273,000 65,948,000 169,874,000 14,608,000 -144,524,000 -224,726,000 155,876,000 115,123,000 -17,400,000 -159,218,000 258,098,000 374,000 71,801,000 -217,369,000 224,115,000 31,786,000 -23,006,000 -22,092,000 -47,606,000 -88,192,000 54,490,000 33,188,000 48,590,000 14,276,000 -37,861,000 25,666,000 19,823,000 18,219,000 364,000 -22,691,000 -11,624,000 -27,979,000 -3,791,000 42,908,000 -53,002,000 -17,153,000 -39,863,000 32,724,000 -2,935,000 7,979,000 -32,298,000 
          net cash from operating activities from continuing operations
        -10,079,000 -666,000 -41,154,000 2,149,000 -12,612,000                                                                                
          cash flows from investing activities:
                                                                                            
          proceeds from matured bonds
        11,492,000 9,056,000 6,786,000 13,328,000 8,488,000 -104,420,000 50,000,000 34,000,000 42,000,000 16,000,000 27,000,000 25,000,000 6,000,000 123,000,000 14,000,000 49,000,000 20,000,000 40,000,000 504,000,000 115,000,000 39,000,000 32,000,000 30,000,000 26,000,000 49,000,000 42,559,000 239,578,000 34,681,000 139,341,000 78,329,000 110,071,000 103,995,000 279,670,000 162,568,000 227,741,000 376,267,000 355,674,000 287,655,000 297,619,000 226,249,000 299,715,000 230,290,000 -73,360,000 255,664,000 178,791,000 408,870,000 313,674,000 208,133,000 162,763,000 150,501,000 159,862,000 202,806,000 116,923,000 198,174,000 143,054,000 243,137,000 161,489,000 176,371,000 166,191,000 154,654,000 157,206,000 354,474,000 258,238,000 523,901,000 476,157,000 431,314,000 437,058,000 472,143,000 452,799,000 417,388,000 719,371,000 365,385,000 383,511,000 475,835,000 374,374,000 290,844,000  750,199,000 333,507,000  1,570,333,000 607,904,000 1,586,991,000 1,078,238,000 
          purchases of bonds
        -27,258,000 -1,102,000 -1,728,000 -11,757,000 -10,990,000 297,530,000 -143,000,000 -143,000,000 -72,000,000 -124,000,000 -65,000,000 -122,000,000 -104,000,000 -130,000,000 -84,000,000 -156,000,000 -33,000,000 -57,000,000 -58,000,000 -100,000,000 -128,000,000 -131,000,000 -159,000,000 -535,000,000 -150,000,000 -439,360,000 -244,171,000 -182,556,000 -179,474,000 -184,765,000 -86,448,000 -77,469,000 -573,660,000 -546,891,000 -439,473,000 -488,346,000 -670,143,000 -413,468,000 -1,002,328,000 -311,206,000 -919,361,000 -625,507,000 -503,908,000 -243,006,000 -197,512,000 -152,537,000 -266,683,000 -182,008,000 -295,398,000 -491,698,000 -258,757,000 -205,418,000 -244,018,000 -219,108,000 -525,985,000 -135,770,000 -602,823,000 -899,373,000 -197,219,000 -539,744,000 -202,435,000 -101,981,000 -1,099,009,000 -1,917,351,000 -379,219,000 -1,499,930,000 -880,851,000 -980,241,000 -702,048,000 -673,868,000 -2,156,408,000 -1,206,581,000 -1,048,370,000 -1,084,991,000 -2,010,932,000 -961,609,000  -2,776,072,000 -1,272,364,000 5,544,881,000 -3,849,511,000 -2,387,615,000 -4,599,837,000 -3,167,562,000 
          change in short-term investments
        54,169,000 149,409,000 -193,127,000 -1,006,000 25,972,000 -45,171,000 8,000,000 68,000,000 71,000,000 -7,000,000 -45,000,000 24,000,000 146,000,000 6,000,000 -56,000,000 112,000,000 -114,000,000 -27,000,000 49,000,000 -18,000,000 94,000,000 91,000,000 105,000,000 -105,000,000 67,000,000 106,605,000 135,819,000 -477,910,000 131,290,000 -169,408,000 -71,402,000 236,262,000 -212,683,000 -156,642,000 83,550,000 -300,653,000 205,084,000 100,538,000 -210,971,000 -167,710,000 139,085,000 56,016,000 221,711,000 -106,274,000 51,809,000 296,592,000 -116,237,000 -110,751,000 41,055,000 242,227,000 8,843,000 -83,629,000 -91,049,000 -102,968,000 2,087,805,000 -1,640,578,000 382,937,000 -282,872,000 -45,982,000 438,139,000 -119,963,000 156,451,000 62,176,000 -673,854,000 -192,906,000 -394,154,000 -21,783,000 41,563,000 -33,996,000 -35,965,000 -37,907,000 268,143,000 -296,937,000 57,785,000 195,327,000 93,017,000 -74,344,000 12,198,000 23,931,000 -227,373,000 6,616,000 180,850,000 277,633,000 194,576,000 
          net cash from investing activities from continuing operations
        37,708,000 -65,435,000 247,341,000 -3,309,000 21,339,000                                                                                
          cash flows from financing activities:
                                                                                            
          payments for purchases of common stock held in treasury
         -26,641,000 -179,000 -3,122,000                                                                                
          payments for long-term debt
        -625,000                                                                                    
          tax payments related to shares withheld for share-based compensation plans
        -572,000 -3,618,000 -173,000 90,000 -1,606,000 308,000 -1,000,000 3,000,000 -3,000,000 -5,000,000 -1,000,000 -3,000,000 -6,000,000 -3,000,000 -412,000 -2,198,000 -91,000 -1,025,000 -1,268,000                                                  
          distributions to noncontrolling interest holders
        -553,000 -2,783,000 -497,000 -186,000 -708,000 -391,000 -1,000,000 -1,000,000 -1,000,000   -2,000,000                                                                     
          acquisitions of noncontrolling interest shares
        -383,000 -67,309,000                                                                                  
          net cash from financing activities from continuing operations
        -2,133,000 84,428,000 -200,979,000 -4,311,000 -5,436,000                                                                                
          effect of foreign exchange on cash and cash equivalents - continuing operations
        -399,000 -4,000 176,000 194,000 1,094,000                                                                                
          net cash from continuing operations
        25,097,000 16,863,000 5,384,000 -5,277,000 4,385,000                                                                                
          cash, cash equivalents, and restricted cash at beginning of period - continuing operations
        68,440,000 47,275,000                                                                                
          cash, cash equivalents, and restricted cash at end of period - continuing operations
        93,537,000 18,323,000 5,384,000 -5,277,000 51,660,000                                                                                
          net cash from operating activities from discontinued operations
         36,877,000 -9,053,000 43,904,000                                                                                
          net cash from investing activities from discontinued operations
         12,045,000 44,517,000 13,150,000                                                                                
          net cash from financing activities from discontinued operations
         -48,290,000 -46,485,000 -48,369,000                                                                                
          effect of foreign exchange on cash and cash equivalents - discontinued operations
           250,000 225,000                                                                                
          net cash from discontinued operations
         157,000 -10,771,000 8,910,000                                                                                
          cash, cash equivalents, and restricted cash at beginning of period - discontinued operations
         -1,000 66,077,000                                                                                
          cash, cash equivalents, and restricted cash at end of period - discontinued operations
           -10,771,000 74,987,000                                                                                
          cash paid during the period for:
                                                                                            
          interest on debt
        1,999,000                                                                                    
          income taxes
        1,483,000                                13,544,000 7,717,000 8,295,000  2,436,000 1,185,000 6,477,000 5,491,000 4,933,000  107,000 229,000 1,117,000              -2,939,000 -288,000 24,368,000 8,500,000 26,020,000 46,015,000 135,300,000 784,000 52,215,000 77,736,000 112,350,000 5,885,000 60,880,000 30,862,000 92,950,000 1,235,000 48,830,000 71,170,000 10,720,000 47,244,000 100,000,000 15,000,000 122,500,000 112,500,000 
          non-cash investing and financing activities:
                                                                                            
          noncontrolling interests acquired in connection with put / call option exercises
        43,644,000                                                                                    
          proceeds from sales of bonds
         1,305,000    -187,006,000 167,000,000 -4,000,000 30,000,000 27,000,000 6,000,000 44,000,000 63,000,000 69,000,000 67,000,000 246,000,000 141,000,000 110,000,000 9,000,000 73,000,000 44,000,000 135,000,000 98,000,000 655,000,000 221,000,000 362,764,000 48,194,000 641,032,000 155,990,000 468,021,000 327,417,000 296,078,000 637,675,000 579,966,000 305,541,000 410,459,000 152,323,000 169,013,000 136,087,000 92,556,000 487,462,000 276,555,000 222,437,000 120,603,000 158,662,000 6,729,000 392,257,000 35,024,000 284,599,000 110,161,000 147,227,000 93,191,000 99,387,000 9,791,000 1,209,812,000 1,129,824,000 698,893,000 1,688,278,000 644,915,000 681,380,000 2,787,169,000 2,148,024,000 1,253,338,000 1,506,056,000 609,927,000 199,600,000 2,416,000 223,378,000 58,266,000 37,912,000 649,112,000 104,725,000 509,675,000 646,379,000 862,159,000 171,086,000 -2,341,151,000 1,704,361,000 805,871,000 -2,628,802,000 1,604,622,000 545,127,000 1,525,160,000 791,622,000 
          proceeds from sales of other invested assets
             -100,375,000 60,000,000 34,000,000 7,000,000 20,000,000 81,000,000 67,000,000 41,000,000 24,000,000 34,000,000 63,000,000 45,000,000 -36,000,000 14,000,000 13,000,000 48,000,000 -3,000,000 16,000,000 118,000,000 243,000,000 24,083,000 46,726,000 1,749,000 47,322,000 60,122,000 20,075,000 31,327,000 134,894,000 56,452,000 121,353,000 -734,000 97,004,000 32,442,000 2,991,000 50,645,000 36,543,000 36,894,000                                           
          purchases of other investments
                                                                                          
          acquisitions, net of cash acquired
         -218,529,000    -28,776,000                                                                              
          proceeds from sale of subsidiary
                                                                                           
          proceeds from long-term debt
                                                                                            
          proceeds from short-term debt
                                                                                           
          issuance of equity interest in subsidiary
                                                                                            
          payments for extinguishment of short-term debt
                                                                                           
          issuance of warrants
                                                                                           
          octave common stock issued as partial consideration to acquire octave ventures
                                                                                            
          cash disposed of related to sale of discontinued operations
                                                                                            
          amortization of bond premium and discount
           -64,000 -63,000 12,704,000 -5,000,000 -5,000,000 -3,000,000 -5,000,000 -4,000,000 -3,000,000 -3,000,000 -3,000,000 -2,000,000 -3,000,000 -3,000,000 -4,000,000 -3,000,000 -3,000,000 -3,000,000 -3,000,000 -4,000,000 -4,000,000 -4,000,000 -4,196,000 -43,249,000 -11,846,000 -16,354,000 -17,816,000 -25,175,000 -77,427,000 -50,721,000 -47,002,000 -36,178,000 -47,105,000 -46,603,000 -30,017,000 -26,336,000 -35,056,000 -31,477,000 -27,940,000 39,181,000 -42,421,000 -25,542,000 -42,258,000 -57,060,000 -64,542,000 -52,002,000 -47,979,000 -50,894,000 -35,439,000 -22,439,000 -24,838,000 -22,011,000 -56,596,000 -72,094,000 -72,203,000 -47,300,000 -24,269,000 -22,605,000 -13,763,000 497,000 -897,000 75,000 83,000 947,000 138,000 644,000 1,508,000 1,189,000 -53,000 160,000 -3,321,000 379,000 46,000  -2,958,000 -3,690,000  6,915,000 3,720,000 3,891,000 1,720,000 
          premium receivables
           -13,418,000 -18,813,000 40,671,000 -25,000,000 -18,000,000 -9,000,000 -13,000,000 -1,000,000 -4,000,000 -3,000,000 -3,000,000 45,000,000 6,000,000 6,000,000 4,000,000 18,000,000 12,000,000 14,000,000 20,000,000 11,000,000 13,000,000 27,463,000 45,931,000 7,979,000 21,473,000 37,395,000 26,831,000 5,601,000 53,827,000 -252,000 8,630,000 46,284,000 63,286,000 13,264,000 49,497,000 41,478,000 48,608,000 34,907,000 -10,790,000 77,523,000 135,209,000 74,044,000 87,662,000 110,943,000 74,714,000 -178,268,000 365,995,000 131,676,000 380,215,000 -13,458,000 152,193,000 776,612,000                             
          depreciation
             345,000 1,000,000 1,000,000 1,000,000                                                                          
          accrued interest payable
             -37,440,000 15,000,000 13,000,000 12,000,000 12,000,000 13,000,000 11,000,000 -37,000,000 -206,000,000 24,000,000 24,000,000 24,000,000 28,000,000 30,000,000 22,000,000 23,000,000 24,000,000 23,000,000 23,000,000 23,000,000 22,451,000 13,425,000 28,971,000 32,103,000 66,698,000 -6,641,000 -82,992,000 20,719,000 1,710,000 4,866,000 21,238,000 20,620,000 8,429,000 16,152,000 -4,007,000 18,269,000 22,235,000 -2,032,000 17,543,000 18,727,000 17,124,000 26,741,000 26,684,000 29,007,000 26,711,000 28,064,000 24,679,000 -29,267,000 32,630,000 11,275,000 -55,000 8,659,000 -25,569,000 9,614,000 -41,488,000 1,478,000 -13,149,000 12,791,000 -45,757,000 -3,181,000 22,769,000 -9,830,000 -1,444,000 5,185,000 29,926,000 -10,229,000 -19,645,000 28,614,000 11,059,000 13,133,000 -15,669,000  -17,024,000 -26,929,000  -13,837,000 -26,631,000 -13,947,000 -5,595,000 
          amortization of intangible assets
             -15,398,000 12,000,000 9,000,000 12,000,000 8,000,000 8,000,000 6,000,000 7,000,000 13,000,000 6,000,000 14,000,000 14,000,000 11,000,000 11,000,000 14,000,000 19,000,000                                                                
          net investment gains, including impairments
             3,497,000 1,000,000 -3,000,000 -1,000,000 15,000,000 -1,000,000 4,000,000 4,000,000 -14,000,000 -7,000,000 -10,000,000                                                                    
          proceeds from sale of subsidiary, net of cash transferred
             119,000                                                                               
          net income attributable to common stockholders
              -27,000,000 -1,000,000 20,000,000 -15,000,000 66,000,000 -14,000,000 -33,000,000 175,000,000 340,000,000 5,000,000 2,000,000 -22,000,000 17,000,000 -29,000,000 17,000,000        -20,459,000 -103,845,000 4,313,000 305,704,000     101,474,000 58,647,000 9,415,000                                              
          redeemable noncontrolling interest
              2,000,000 -1,000,000 -1,000,000                                                                      
          variable interest entity activities
              -3,000,000 1,000,000 -3,000,000   1,000,000 -7,000,000 1,000,000 7,000,000 -22,000,000 -2,000,000 -3,000,000   -2,000,000 -3,000,000 -11,244,000 -3,294,000 -15,921,000 -454,000 -1,831,000 -577,000 -574,000 4,049,000 1,219,000 -3,701,000 -2,026,000 -2,057,000 -8,987,000 27,163,000 21,435,000 -6,962,000 5,542,000 33,728,000 -38,326,000 -884,000 -6,137,000 -5,536,000 -15,220,000 265,604,000 -55,008,000 -2,353,000 6,125,000 111,815,000 -26,377,000 38,546,000 492,704,000                             
          net cash from operating activities
              -4,000,000 14,000,000 18,000,000 88,000,000 11,000,000 24,000,000 77,000,000 1,276,000,000 48,000,000 2,000,000 9,000,000 5,000,000 -53,000,000 -43,000,000 -40,000,000 -8,000,000 -55,000,000 -25,000,000 -87,000,000 -31,370,000 -169,733,000 -95,128,000 -125,320,000 -106,355,000 -120,026,000 -1,191,562,000 -117,728,000 -158,357,000 -2,646,000 18,008,000 -44,777,000 42,629,000 827,680,000 42,569,000 5,580,000 38,525,000 -37,767,000 77,330,000 -208,298,000 -441,029,000 -4,921,000 40,350,000 -195,341,000 -8,665,000 124,748,000 82,815,000 77,817,000   427,098,000 -515,013,000 -608,031,000 -344,050,000 -383,658,000 -638,038,000 -899,749,000 -26,514,000 141,250,000 117,496,000 383,695,000 141,217,000 302,976,000 274,296,000 105,970,000 216,633,000 306,234,000 299,382,000 225,991,000 194,936,000 287,189,000 -631,101,000 540,985,000 218,935,000 -752,881,000 508,789,000 176,708,000 481,996,000 210,884,000 
          capital expenditures
                
          free cash flows
              -4,000,000 14,000,000 18,000,000 88,000,000 11,000,000 24,000,000 77,000,000 1,276,000,000 48,000,000 2,000,000 9,000,000 5,000,000 -53,000,000 -43,000,000 -40,000,000 -8,000,000 -55,000,000 -25,000,000 -87,000,000 -31,370,000 -169,733,000 -95,128,000 -125,320,000 -106,355,000 -120,026,000 -1,191,562,000 -117,728,000 -158,357,000 -2,646,000 18,008,000 -44,777,000 42,629,000 827,680,000 42,569,000 5,580,000 38,525,000 -37,767,000 77,330,000 -208,298,000 -441,029,000 -4,921,000 40,350,000 -195,341,000 -8,665,000 124,748,000 82,815,000 77,817,000   427,098,000 -515,013,000 -608,031,000 -344,050,000 -383,658,000 -638,038,000 -899,749,000 -26,514,000 141,250,000 117,496,000 383,695,000 141,217,000 302,976,000 274,296,000 105,970,000 216,633,000 306,234,000 299,382,000 225,991,000 194,936,000 287,189,000 -631,101,000 540,985,000 218,935,000 -752,881,000 508,789,000 176,708,000 481,996,000 210,884,000 
          purchases of other invested assets
              -38,000,000 -12,000,000 -82,000,000 -18,000,000 -20,000,000 -28,000,000 -14,000,000 -13,000,000 -25,000,000 -49,000,000 -25,000,000 -30,000,000 -17,000,000 -39,000,000 -41,000,000 -50,000,000 -24,000,000 -206,000,000 -195,000,000 -17,562,000 -88,827,000 -28,559,000 -46,538,000 -74,938,000 -7,104,000 -11,758,000 -113,070,000 -21,814,000 -139,561,000 -30,843,000 -104,939,000 -130,098,000 -15,690,000 -20,217,000 -10,176,000 -20,611,000                                           
          change in cash collateral
              -7,000,000 5,000,000 -13,000,000 8,000,000 -21,000,000 -16,000,000                                                                        
          change in consolidated vie cash collateral
              -15,000,000 -186,000,000 6,000,000 -19,000,000 -2,000,000 2,000,000 254,000,000                                                                        
          proceeds from paydowns of consolidated vie assets
              43,000,000 41,000,000 43,000,000 38,000,000 48,000,000 56,000,000 57,000,000 378,000,000 43,000,000 36,000,000 47,000,000 37,000,000 47,000,000 37,000,000 50,000,000 36,000,000 44,000,000 32,000,000 66,000,000 389,846,000 54,913,000 67,172,000 161,613,000 49,277,000 58,066,000 79,917,000                                                     
          net cash from investing activities
              -80,000,000 -171,000,000 51,000,000 -86,000,000 32,000,000 48,000,000 441,000,000 431,000,000 -5,000,000 304,000,000 136,000,000 31,000,000 558,000,000 71,000,000 116,000,000 36,000,000 126,000,000 26,000,000 244,000,000 478,859,000 200,420,000 112,155,000 338,496,000 234,009,000 358,355,000 656,996,000 178,652,000 127,888,000 167,577,000       -84,196,000 -104,739,000 -63,965,000 221,613,000 515,067,000 310,018,000 -8,718,000 198,121,000 13,998,000 8,504,000 7,403,000 -21,464,000 -102,988,000 2,989,756,000 -393,596,000 733,575,000 813,918,000 1,787,669,000 1,250,296,000 2,744,997,000 2,583,251,000 477,837,000 -556,389,000 519,265,000 -1,001,198,000 -991,460,000 55,206,000 -428,237,000 -253,364,000 -514,645,000 -315,859,000 -924,643,000 103,975,000 -434,888,000 -208,636,000 228,419,000 -269,607,000 -186,938,000 541,507,000 -572,012,000 -667,830,000 -1,214,038,000 -1,154,636,000 
          payments for purchases of common stock
                 -2,000,000                                                                        
          payments for redemption of tier 2 notes
                 -97,000,000                                                                        
          payments of consolidated vie liabilities
              -44,000,000 -41,000,000 -46,000,000 -30,000,000 -50,000,000 -61,000,000 -174,000,000 -187,000,000 -45,000,000 -310,000,000 -49,000,000 -37,000,000 -48,000,000 -37,000,000 -48,000,000 -35,000,000 -44,000,000 -33,000,000 -66,000,000 -418,186,000 -29,020,000 -63,022,000 -161,613,000 -49,276,000 -58,067,000 -79,917,000                                                     
          net cash from financing activities
              103,000,000 -42,000,000 -47,000,000 -31,000,000 -49,000,000 -67,000,000 -276,000,000 -1,684,000,000 -45,000,000 -382,000,000 -52,000,000 -34,000,000 -516,000,000 -38,000,000 -69,000,000 -43,000,000 -55,000,000 -59,000,000 -146,000,000 -425,414,000 -9,554,000 -75,602,000 -183,461,000 -119,462,000 -232,237,000 -50,218,000 -7,737,000 -32,407,000 -137,647,000 -4,789,000     -49,870,000 1,000 772,000 -4,067,000 -59,543,000 -32,985,000 -296,016,000 -7,700,000 -8,097,000 -1,396,000 -123,499,000 -92,089,000 -116,529,000    -254,886,000 -1,186,592,000 -421,226,000 -866,583,000 -2,091,528,000 -1,696,718,000 -444,956,000 390,435,000 -539,642,000 608,588,000 854,483,000 -358,561,000 144,303,000 156,781,000 304,310,000 7,827,000 625,088,000 -338,058,000 234,813,000 -56,811,000 401,516,000 -262,663,000 -36,400,000 78,259,000 64,387,000 516,362,000 687,804,000 904,303,000 
          effect of foreign exchange on cash, cash equivalents and restricted cash
                                -409,000 -213,000 176,000  -113,000 -261,000 -278,000                                                     
          net cash flow
              20,000,000 -199,000,000 21,000,000 -28,000,000 -7,000,000 5,000,000 243,000,000 24,000,000 -2,000,000 -77,000,000 93,000,000 2,000,000 -10,000,000 -10,000,000 6,000,000 -15,000,000 16,000,000 -57,000,000 10,000,000 21,666,000 20,920,000 -58,399,000 29,964,000 8,079,000 5,831,000 -585,062,000 52,780,000 -64,534,000 27,747,000 69,807,000 -1,826,000 -6,098,000 -6,602,000 -6,866,000 -47,262,000 -45,670,000 -141,734,000 9,298,000 -46,228,000 41,053,000 9,081,000 23,932,000 -5,317,000 3,937,000 9,753,000 -1,871,000 -60,176,000 12,996,000 -58,131,000 2,729,000 -36,324,000 -980,705,000 1,022,393,000 55,000 15,431,000 -13,216,000 6,367,000 -24,704,000 97,119,000 -8,915,000 4,240,000 -379,000 -9,638,000 9,387,000 6,298,000 -1,798,000 -173,000 -8,092,000 -5,139,000 21,742,000 -1,166,000 8,715,000 -4,403,000 -11,073,000 1,164,000 25,240,000 -44,238,000 -39,449,000 
          cash, cash equivalents, and restricted cash at beginning of period
              274,000,000 61,000,000 23,000,000 35,000,000 81,000,000 83,493,000 624,681,000                                                     
          cash, cash equivalents, and restricted cash at end of period
              20,000,000 -199,000,000 296,000,000 -28,000,000 -7,000,000 5,000,000 304,000,000 23,000,000 -1,000,000 -77,000,000 116,000,000 1,000,000 -10,000,000 -10,000,000 42,000,000 -15,000,000 16,000,000 -57,000,000 91,000,000 21,666,000 20,920,000 25,094,000 29,964,000 8,079,000 5,831,000 39,619,000                                                     
          repurchase of auction market preferred shares
                                                                                            
          loss on extinguishment of debt
                     -24,000,000      -33,000,000           -3,115,000   -2,741,000                                                  
          proceeds from issuance of sitka aac note
                                                                                           
          proceeds from issuance of surplus notes
                         4,000,000           6,476,000                                                        
          paydowns of lsni ambac note
                                                                                            
          payments for debt issuance costs
                                   -9,221,000                                                     
          payments for purchase of surplus notes
                                                                                            
          payments for redemption of sitka aac note
                                                                                            
          payments for auction market preferred shares
                                                                                           
          effect of foreign exchange on cash and cash equivalents
                                        -407,000 -1,658,000 463,000                                                  
          derivative assets and liabilities
                  -4,000,000 11,000,000 14,000,000 18,000,000 -8,000,000 -8,000,000 -46,000,000 -6,000,000 5,000,000 -22,000,000 -9,000,000 -6,000,000 -11,000,000 32,000,000 5,722,000 -13,069,000 12,305,000 -17,450,000 82,000 -558,000 438,000 -510,000                                                    
          (gain) loss on extinguishment of debt
                                                                                        
          depreciation and amortization
                     1,000,000   1,000,000       70,000 127,000 159,000 168,000 168,000 182,000 181,000 233,000 263,000 270,000 300,000 285,000 332,000 303,000 647,000 791,000 748,000 -226,000 727,000 772,000 748,000 726,000 820,000 809,000 738,000 1,406,000 780,000 959,000 968,000 972,000 746,000 760,000 769,000 744,000 710,000 746,000 809,000 805,000 801,000 685,000 663,000 669,000 678,000 738,000 696,000 756,000 675,000 1,068,000 1,239,000 1,332,000 648,000  1,520,000 778,000  1,614,000 820,000 2,608,000 1,724,000 
          change in cash collateral receivable
                     -16,000,000 4,000,000 2,000,000 54,000,000 -2,000,000   11,000,000  11,000,000 43,000,000 -56,000,000 10,063,000 8,184,000 56,771,000 -68,689,000 10,172,000 1,760,000 -979,000 30,081,000 63,559,000 9,615,000                                                  
          payments for extinguishment of surplus notes
                                                                                          
          current income taxes
                         -1,000,000 -3,000,000 8,000,000 16,000,000 -2,000,000 -5,000,000 -5,151,000 28,768,000 4,232,000 -14,521,000 2,587,000 -15,125,000 -8,439,000 -7,842,000 733,000 11,550,000 -2,121,000 12,825,000 1,486,000 -2,463,000 -2,655,000 -3,368,000 3,023,000 -310,000 496,000 -601,000 627,000 743,000 300,000 -2,823,000 75,097,000 -1,449,000 2,350,000 85,000 65,000 -122,000 443,944,000 -472,005,000 241,062,000 1,149,000 1,025,000 561,163,000 -126,040,000 -801,836,000 76,218,000 65,514,000 -16,915,000 -70,031,000 69,338,000 20,639,000 -58,413,000 4,990,000 65,978,000 21,526,000 -8,304,000 -47,177,000 50,499,000  -3,791,000 9,593,000  -19,335,000 16,734,000 -61,470,000 -79,395,000 
          net realized investment gains
                         -3,000,000 -3,000,000 1,000,000 -2,000,000 -2,000,000 -2,000,000 -10,000,000 -8,000,000 -18,471,000 -35,860,000 -17,233,000 -29,413,000 -30,201,000 -47,148,000 -4,862,000 -6,150,000 -4,180,000 4,896,000 -11,536,000 -11,749,000 -14,897,000 -1,102,000 -2,106,000 -54,101,000 -16,289,000 27,588,000 -46,060,000    -392,000 -12,341,000 -5,084,000 -591,000 -2,450,000 -6,100,000 -1,996,000 -94,806,000 -56,549,000 -66,885,000       147,580,000 31,077,000 -4,163,000 -1,191,000 -6,601,000 -9,631,000 -7,965,000 -44,411,000 -5,124,000 2,191,000 -9,533,000 587,000 -1,866,000  -21,026,000 -17,798,000  -31,669,000    
          acquisition of xchange, net of cash acquired
                                                                                            
          proceeds from issuance of ambac uk debt
                                                                                           
          issuance of auction market preferred shares of ambac assurance
                                 16,054,000 2,764,000                                                         
          paydowns of ambac note
                          -1,625,000,000 -16,000,000 -6,000,000 -12,000,000 -26,000,000 -77,000,000 -6,816,000 -8,768,000 -13,146,000 -28,324,000 -72,281,000                                                       
          noncontrolling interest in subsidiaries’ earnings
                                           -198,000 -36,000   -44,000 160,000 107,000 -352,000 -47,000 -275,000 -171,000 -2,232,000 2,000 15,000 -2,000 14,000 33,000 76,000 13,000 -15,000 -11,000 13,000 -14,000 11,000 -13,000                         
          dividends paid to noncontrolling interest holders
                                                                                            
          exchange for auction market preferred shares
                                                                                           
          amortization of insurance intangible assets
                             16,000,000 14,000,000 14,000,000 13,000,000 17,421,000 226,242,000 36,278,000 28,982,000 26,421,000 23,242,000 28,636,000 45,690,000 33,471,000 37,525,000 40,152,000 44,553,000 39,013,000 50,890,000 39,680,000 37,432,000 31,714,000                                           
          net proceeds from issuance of tier 2 notes
                                                                                          
          paydowns of a secured borrowing
                                    -65,196,000 -8,797,000 -7,737,000 -6,574,000 -10,355,000 -4,176,000 -11,676,000 -4,759,000 -8,871,000                                              
          net mark-to-market (gains) losses
                              -1,000,000 2,000,000   -382,000 284,000 -151,000   -45,000   -1,351,000 -1,507,000 -3,722,000 -12,614,000 -35,259,000 2,918,000 -6,607,000 -34,868,000 -10,278,000           -2,967,920,000 179,802,000                             
          other-than-temporary impairment charges
                                 42,000 29,000 1,659,000 266,000 1,014,000 299,000 13,510,000 1,763,000 3,942,000 2,191,000 2,853,000 7,441,000 9,334,000 9,150,000 3,119,000 10,392,000   237,000 354,000 2,328,000 3,071,000 33,665,000 10,887,000 17,578,000 1,713,000 11,304,000 6,584,000 10,566,000 31,349,000 118,054,000 43,171,000                           
          proceeds from warrant exercises
                                                                                        
          net mark-to-market losses
                                       452,000   -853,000          26,464,000 -24,496,000     -20,063,000 14,226,000     -792,144,000 -2,865,756,000 -35,597,000 -1,529,007,000 -326,558,000 1,901,080,000 -959,004,000 1,767,933,000 5,229,279,000 757,555,000                   
          investment income due and accrued
                                    -896,000 1,430,000 8,359,000 -3,926,000 4,119,000 3,005,000 -1,250,000 -605,000 -327,000 304,000 -122,000 166,000 21,000 3,022,000 -3,555,000 5,798,000 -2,560,000 5,469,000 -2,820,000 5,497,000 -4,320,000 4,554,000 -5,847,000 5,351,000 -7,720,000 10,649,000 -1,420,000 26,487,000 -10,296,000 14,941,000 -5,592,000 40,521,000 23,198,000 34,415,000 -28,413,000 56,768,000 -27,522,000 7,992,000 -28,593,000 38,585,000 -17,705,000 -590,000 -31,990,000 28,417,000 -23,064,000 3,768,000 -20,552,000 23,575,000  17,078,000 33,482,000  495,000 20,495,000 16,502,000 -11,670,000 
          payments for investment agreement draws
                                        -82,358,000 25,000   -14,000,000 -49,872,000                                         -504,927,000 -1,378,861,000 -951,991,000 
          cost of warrants acquired
                                           -613,000 -494,000                                                
          loans
                                        -265,000 -5,888,000 -77,000 353,000 102,000 494,000 97,000 175,000 220,000 -71,000 -282,000 512,000 1,177,000 -227,000 9,090,000 -247,000 1,039,000 236,000 126,000 -230,000 831,000 49,850,000 241,000 9,321,000 77,575,000 3,898,000 -18,395,000 419,245,000 3,126,000 -2,554,000 2,623,000 29,482,000 2,961,000 -9,273,000 -258,740,000 22,798,000 -136,910,000 5,026,000 161,191,000 30,033,000 -71,711,000 5,192,000 21,986,000 39,873,000  2,552,000 5,022,000  23,362,000 5,200,000 52,795,000 -31,019,000 
          proceeds from sales of senior surplus notes
                                                                                            
          payments for extinguishment of long-term debt
                                      -191,258,000 -25,833,000 -43,666,000 -8,097,000 -11,453,000                                            
          net proceeds from issuance of tier ii notes
                                       240,000,000                                                     
          net income attributable to common shareholders
                                        -190,905,000       -390,987,000 214,711,000 155,942,000 -76,618,000 282,299,000 143,576,000 157,544,000 -811,118,000 253,320,000       -57,559,000 -690,051,000                             
          cash and cash equivalents at beginning of period
                                        91,025,000 35,744,000 73,903,000                                            
          cash and cash equivalents end of period
                                        52,780,000 -64,534,000 118,772,000 69,807,000 -1,826,000 -6,098,000 29,142,000 -6,866,000 26,641,000                                            
          supplemental disclosure of cash flow information:
                                                                                            
          interest on long-term debt and investment agreements
                                        854,000 8,680,000 28,791,000                                                  
          non-cash financing activities:
                                                                                            
          decrease in long-term debt as a result of an exchange for investment securities
                                        55,426,000                                                  
          impairment of goodwill
                                                                                            
          reorganization items
                                                 23,000 -1,635,000 2,059,000 2,735,000 1,252,000 767,000 2,461,000 10,067,000 8,519,000 6,470,000 24,805,000                                 
          proceeds from the sale of junior surplus notes of the segregated account
                                                                                            
          net proceeds received from a secured borrowing
                                                                                            
          net realized (gains) losses on extinguishment of debt
                                            -24,000 -3,586,000 -1,235,000                                              
          change in swap collateral receivable
                                            38,980,000 -61,178,000 -29,788,000 -36,742,000 -37,239,000 -35,410,000 9,149,000 1,740,000 6,218,000 11,026,000 -14,655,000 41,046,000 5,563,000 1,317,000 -52,156,000 -104,000 92,895,000 -40,200,000 67,432,000 -2,984,000 14,613,000 130,328,000                           
          net cash (used in) investing activities
                                            57,018,000 -16,274,000 -813,958,000  -2,972,000                                            
          proceeds received from a secured borrowing
                                                                                            
          effect of foreign exchange rate changes on cash and cash equivalents
                                                                                            
          interest on secured borrowing
                                            1,261,000 681,000 1,372,000                                              
          interest on investment agreements
                                            136,000 153,000 146,000 102,000 88,000 202,000 -1,521,000 1,724,000 902,000 1,792,000 1,498,000 3,072,000 825,000 3,269,000 706,000 3,656,000  6,646,000 2,582,000 7,947,000 5,434,000 10,849,000 5,909,000 21,678,000 48,689,000 73,996,000 49,302,000 104,507,000 115,189,000 91,990,000 117,783,000 83,418,000 100,565,000 104,226,000 74,804,000 79,986,000             
          net cash (used in) financing activities
                                             -32,453,000 -20,324,000                -267,556,000 -30,773,000                             
          cash payments related to reorganization items:
                                                                                            
          professional fees paid for services rendered in connection with the chapter 11 proceeding
                                                 81,000 -2,451,000 3,246,000 1,479,000 706,000 5,315,000 1,641,000 12,847,000 6,681,000 6,268,000 5,457,000                                 
          losses on extinguishment of debt
                                                93,000                                            
          proceeds from warrant exercise
                                                2,000 1,000                                           
          deferred acquisition costs
                                                   6,854,000 6,658,000 6,089,000 7,094,000 4,509,000 1,919,000 12,796,000 9,521,000 2,903,000 1,322,000 11,287,000 10,147,000 6,299,000 20,423,000 -89,759,000 -21,105,000 10,254,000 14,559,000 6,039,000 11,972,000 15,840,000 21,980,000 -6,384,000 -7,953,000 -4,719,000 -15,958,000 -6,251,000 3,289,000 -12,292,000 -461,000 -2,929,000 2,838,000 -16,877,000  -15,003,000 -1,227,000  -591,000 -385,000 -9,241,000 -6,868,000 
          gains on extinguishment of debt
                                                                                            
          paydowns of variable interest entity secured borrowing
                                                  757,000 -4,067,000                                         
          interest on variable interest entity secured borrowing
                                                  -128,000 218,000 311,000 334,000 498,000 429,000                                     
          interest on surplus notes
                                                                                            
          cash at january 1
                                                 77,370,000  43,837,000 15,999,000       112,079,000     123,933,000 31,868,000 -676,000 28,295,000 19,957,000 -24,216,000 24,449,000 24,449,000      
          cash at march 31
                                                 31,700,000  53,135,000    39,931,000        114,808,000        99,229,000    31,489,000    26,497,000    41,699,000   20,046,000      
          •
                                                                                            
          payments for investment and repurchase agreement draws
                                                    -53,663,000 -28,489,000 -104,214,000 -420,000                                     
          cash at beginning on period
                                                                                            
          cash at ending of period
                                                                                            
          cash receipts and payments related to reorganization items:
                                                                                            
          enterprise value
                                                                                            
          add: fair value of liabilities
                                                                                            
          add: fair value of noncontrolling interest
                                                                                            
          reorganization value allocated to assets
                                                                                            
          less: fair value of identified tangible and intangible assets
                                                                                            
          reorganization value in excess of fair value of assets
                                                                                            
          other investments
                                                   -113,712,000                                         
          cash paid during the year for:
                                                                                            
          debt obligations and accrued interest payable
                                                   1,690,312,000                                        
          accounts payable
                                                   14,329,000                                         
          consolidated liabilities subject to compromise
                                                   1,704,641,000  -3,000                                       
          payable to non-debtor subsidiaries
                                                                                           
          debtor’s liabilities subject to compromise
                                                   1,704,641,000  -3,000                                       
          losses (gains) on extinguishment of debt
                                                    -165,000                                       
          proceeds received from a newly established variable interest entity
                                                                                            
          proceeds from issuance of investment and repurchase agreements
                                                                                            
          payments for extinguishment of debt
                                                                                            
          net cash collateral received
                                                                 -72,303,000 28,814,000 2,902,000 -504,853,000 6,696,000   -64,839,000 -19,471,000 79,420,000 -1,728,000 2,891,000 -14,886,000 13,488,000 703,000 3,068,000   5,810,000  36,676,000 26,815,000      
          cash at december 31
                                                                                            
          net realized investment (gains) losses
                                                     -3,162,000                                    -14,251,000   
          paydown of variable interest entity secured borrowing
                                                     -4,496,000 -3,356,000 -7,280,000                                     
          cash at september 30
                                                                                            
          cash at june 30
                                                                                     33,164,000       
          net mark-to-market gains
                                                       10,476,000 -24,518,000                                    
          transfers to restricted cash
                                                                                            
          dividends paid—subsidiary shares to noncontrolling interest
                                                                                            
          interest expense on long-term debt
                                                             17,210,000   26,196,000 18,162,000 26,195,000 30,463,000 26,195,000 30,463,000           14,878,000 27,415,000 26,340,000 18,146,000         
          net loss attributable to common shareholders
                                                         -75,507,000 -102,432,000 -819,279,000 -81,595,000     2,188,257,000 -2,368,794,000 -392,187,000                         
          net loss
                                                         -75,509,000 -102,418,000 -819,246,000 -81,519,000     2,188,243,000 -2,368,783,000 -392,200,000                         
          adjustments to reconcile net loss to net cash from operating activities:
                                                                                            
          loss and loss expense
                                                         -55,992,000 187,936,000 921,429,000  108,306,000 340,463,000 -77,859,000                             
          dividends paid – subsidiary shares to noncontrolling interest
                                                             -1,000 -816,000  -1,894,000 -5,201,000 -5,053,000                         
          proceeds from issuance of investment and payment agreements
                                                         4,000 2,000 24,000 -22,000 84,000 69,000 1,184,000 42,384,000 30,225,000 57,000 23,474,000 44,496,000 22,699,000 12,714,000 4,503,000 643,387,000 929,577,000 807,020,000 121,575,000 763,754,000 279,182,000 1,068,415,000 277,937,000 305,832,000 250,568,000 874,334,000 221,295,000  934,521,000 391,879,000  956,327,000    
          payments for investment and payment agreement draws
                                                         -1,400,000      -31,145,000        -914,624,000  -266,012,000 -166,145,000 -579,758,000  -185,263,000 -588,408,000 -309,548,000  -415,226,000 -466,813,000 -292,223,000  -1,218,540,000 -391,068,000  -1,062,892,000    
          net cash collateral paid/received
                                                         -2,440,000  5,090,000                               
          cash and cash equivalents at january 1
                                                         9,497,000     107,811,000                         
          cash and cash equivalents at september 30
                                                                                            
          cash and cash equivalents at june 30
                                                                                            
          payments for investment and payment draws
                                                           -89,673,000 -109,507,000 -77,593,000   -219,619,000 -212,403,000 -444,896,000 -985,803,000 -2,321,308,000 -1,707,474,000                       
          cash and cash equivalents at march 31
                                                           7,626,000        107,866,000                         
          dividends paid—common stockholders
                                                                                            
          securities sold under agreements to repurchase
                                                                    -139,000 139,000 -100,000,000    128,000,000  37,000,000 -19,000,000 39,000,000      -2,300,000 -62,300,000  8,092,000 140,154,000 -14,366,000 -16,000,000 
          proceeds from issuance of long-term debt
                                                                                 50,000,000         
          proceeds from issuance of subsidiary shares to noncontrolling interest
                                                                                            
          retirement of subsidiary shares to noncontrolling interest
                                                                -9,372,000 -1,806,000                         
          capital issuance costs
                                                                -297,000 -6,836,000 -4,924,000 -3,278,000 -3,260,000 -3,188,000 -1,197,000 -798,000 -887,000 -862,000 -771,000 -971,000 -894,000 -1,007,000 -1,168,000 -1,683,000 -1,177,000  -2,158,000 -1,132,000  -2,471,000 -1,476,000 -6,969,000 -5,767,000 
          proceeds from issuance of common stock
                                                                    -730,000 1,182,762,000                     
          purchases of treasury stock
                                                                    -18,000 -405,000 -26,000 -641,000 -6,000 -20,500,000 -17,084,000 -411,802,000 -59,461,000 -23,443,000 -976,000 -42,823,000 -2,920,000 -165,926,000 -140,103,000 -721,000 -208,000 -51,566,000 -24,992,000 4,936,000 -23,835,000 -7,708,000 -38,654,000 -15,829,000 
          excess tax benefit related to share-based compensation
                                                                    -129,000 -10,291,000   -706,000 637,000 5,249,000 3,331,000 2,761,000 5,576,000 1,064,000 8,418,000             
          cash and cash equivalents at december 31
                                                                                            
          proceeds from the issuance of subsidiary shares to noncontrolling interest
                                                                 100,000,000                         
          adjustments to reconcile net income to net cash from provided by operating activities:
                                                                                            
          net cash (used in) operating activities
                                                                                            
          recoveries from impaired investments
                                                                    252,000 6,206,000 4,692,000 6,636,000               
          cash acquired in consolidation of variable interest activities
                                                                                            
          item 1.
                                                                                            
          net cash collateral paid
                                                               4,000                             
          supplemental disclosures of cash flow information:
                                                                                            
          interest on long-term debt
                                                               18,163,000        24,525,000  24,730,000 20,258,000 12,225,000  12,301,000 36,781,000 36,967,000             
          ceded reinsurance balances payable
                                                                    2,138,000 -1,164,000 -1,582,000 -16,230,000 8,029,000 5,208,000 -1,690,000 804,000 3,120,000 -21,116,000 22,343,000 -8,009,000 4,674,000 -12,424,000 17,803,000 -4,555,000  7,751,000 1,660,000  -1,896,000 -5,358,000 1,102,000 -315,000 
          securities purchased under agreements to resell
                                                                        270,000,000 -270,000,000 273,000,000 -73,000,000 106,000,000 113,000,000 -387,000,000 -7,000,000 72,000,000 256,000,000  11,015,000 -92,985,000  81,210,000 253,816,000 -13,304,000 -2,805,000 
          cash acquired in consolidation of variable interest entities
                                                                                          
          payments for redemption of variable interest entity long-term debt
                                                                -77,288,000                            
          proceeds from sale of treasury stock
                                                                       3,000 1,676,000 17,713,000 7,905,000 11,884,000 36,474,000 3,171,000 9,484,000 19,160,000 5,176,000 6,023,000 249,000 -11,399,000 25,707,000 18,905,000 -4,936,000 35,715,000 9,936,000 38,047,000  
          dividends paid – common stockholders
                                                                                            
          net realized investment losses
                                                                  -841,728,000 711,816,000 -98,953,000                        
          dividends paid
                                                                    -2,880,000 -2,880,000 -2,876,000 -7,168,000 -21,325,000 -21,322,000 -18,382,000 -18,537,000 -19,103,000 -19,074,000 -15,866,000 -15,867,000 -15,801,000 -15,955,000 -13,433,000 -13,616,000 -13,595,000 -23,754,000 -11,830,000 -11,760,000 -21,231,000 -10,602,000 -29,654,000 -19,064,000 
          payments for redemption of long-term debt
                                                                            -26,796,000 -8,014,000 -156,607,000 -8,583,000 50,546,000 -25,567,000           
          proceeds from minority interest
                                                                                            
          background and basis of presentation
                                                                                            
          change in trading account assets
                                                                                            
          loss and loss expenses
                                                                       1,007,095,000  22,690,000 23,838,000 11,041,000  -11,425,000 -7,086,000 -7,576,000  75,926,000 -24,742,000 -812,000  49,524,000       
          proceeds from the issuance of long-term debt
                                                                       228,969,000  5,200,000 275,490,000 393,340,000  50,000,000 50,000,000  50,000,000           
          cash collateral payable
                                                                       3,108,000                     
          excess tax (cost) benefit related to share-based compensation
                                                                       -3,217,000                     
          issuance of common stock
                                                                                1,000 855,000 908,000 5,238,000 38,751,000 17,323,000 14,249,000 11,494,000 132,000 4,288,000 4,284,000 
          cash received during the year for:
                                                                                            
          adjustments to reconcile net income to net cash
                                                                                            
          provided by operating activities:
                                                                                            
          change in trading account
                                                                                            
          jurisdiction
                                                                                            
          united states
                                                                                           
          new york state
                                                                                           
          new york city
                                                                                           
          united kingdom
                                                                                           
          proceeds from the sales of cadre financial services, inc.
                                                                                            
          other liabilities
                                                                            263,870,000                
          total liabilities
                                                                            13,042,815,000                
          accumulated other comprehensive income
                                                                            200,005,000                
          total stockholders’ equity
                                                                                            
          assets:
                                                                                            
          cash
                                                                                            
          loans investment in fixed income securities
                                                                                            
          derivative assets
                                                                                            
          other assets
                                                                                            
          total assets
                                                                                   10,332,236,000         
          liabilities:
                                                                                            
          long-term debt
                                                                                            
          derivative liabilities
                                                                                            
          deferred taxes
                                                                                            
          stockholders’ equity:
                                                                                            
          total liabilities and stockholders’ equity
                                                                                            
          purchases of securitization collateral
                                                                                 45,808,000 -101,600,000         
          2005: fixed income securities:
                                                                                            
          municipal obligations
                                                                                            
          corporate obligations
                                                                                            
          foreign obligations
                                                                                            
          u.s. government obligations
                                                                                            
          u.s. agency obligations
                                                                                            
          mortgage and asset-backed securities
                                                                                            
          short-term
                                                                                            
          fixed income securities pledged as collateral:
                                                                                            
          total
                                                                                            
          2004: fixed income securities:
                                                                                            
          proceeds from the sale of cadre financial services, inc.
                                                                                            
          interest expense on investment agreements
                                                                                 63,345,000 65,120,000 48,788,000  78,713,000 38,713,000  101,447,000  164,261,000 114,631,000 
          cash received during the period for:
                                                                                            
          (dollars in thousands) three months ended september 30,
                                                                                            
          2005:
                                                                                            
          revenues:
                                                                                            
          unaffiliated customers
                                                                                   323,381,000  298,227,000 271,250,000  268,888,000 224,303,000  190,089,000 
          intersegment
                                                                                   198,000  5,599,000 5,717,000  1,218,000 1,770,000  3,954,000 
          total revenues
                                                                                   323,579,000  303,826,000 276,967,000  270,106,000 226,073,000  194,043,000 
          income before income taxes:
                                                                                            
          total income before income taxes
                                                                                   256,848,000  257,801,000 234,271,000  238,729,000 194,592,000  169,754,000 
          2004:
                                                                                            
          (dollars in thousands) nine months ended september 30,
                                                                                            
          net cash collateral (paid) received
                                                                                            
          payment for redemption of long-term debt
                                                                                   -27,336,000         
          (dollars in thousands) three months ended march 31,
                                                                                            
          equity in undistributed net income of subsidiaries
                                                                                            
          net realized losses
                                                                                            
          increase in current income taxes receivable
                                                                                            
          increase in other assets
                                                                                            
          proceeds from maturities of bonds
                                                                                            
          proceeds from the sale of cadre financial services
                                                                                            
          proceeds from issuance of debentures
                                                                                       363,188,000 363,188,000   
          payment for buyback of debentures
                                                                                       -200,000,000    
          contribution to subsidiaries
                                                                                            
          interest expense on debt
                                                                                    11,858,000 27,583,000 15,725,000 11,858,000 26,840,000 14,811,000 38,407,000 17,647,000 
          insurance premiums written
                                                                                            
          year ended december 31, 2002
                                                                                            
          year ended december 31, 2003
                                                                                            
          year ended december 31, 2004
                                                                                            
          net mark-to-market (gains) losses on credit derivative contracts and derivative hedge contracts
                                                                                     -10,322,000 -7,025,000      
          payment for redemption of debentures
                                                                                            
          (dollars in thousands) three months ended june 30,
                                                                                            
          identifiable assets
                                                                                     8,791,608,000 8,638,579,000  7,787,223,000 7,321,128,000  6,318,366,000 
          2003:
                                                                                            
          net realized (gains) losses
                                                                                            
          decrease (increase) in current income taxes receivable
                                                                                            
          decrease (increase) in other assets
                                                                                            
          proceeds from intercompany note
                                                                                            
          year ended december 31, 2001
                                                                                            
          losses and loss adjustment expenses
                                                                                        10,533,000 5,112,000 14,757,000 9,510,000 
          net unrealized losses on credit derivative contracts and derivative hedge contracts
                                                                                        1,446,000    
          cash and cash pledged as collateral at january 1
                                                                                        25,816,000 25,816,000 76,580,000 76,580,000 
          cash and cash pledged as collateral at september 30
                                                                                            
          2002:
                                                                                            
          cash and cash pledged as collateral at june 30
                                                                                        26,980,000   37,131,000 
          net mark-to-market losses on credit derivative contracts and derivative hedge contracts
                                                                                         11,499,000   
          proceeds from issuance of investment agreements
                                                                                         674,586,000 2,105,362,000 1,867,007,000 
          payment agreements
                                                                                         -6,767,000 -5,755,000 -11,464,000 
          cash and cash pledged as collateral at march 31
                                                                                         51,056,000   
          interest expense on investment and payment agreements
                                                                                         83,272,000   
          three months ended march 31,
                                                                                            
          year ended december 31, 2000
                                                                                            
          net securities losses
                                                                                          8,984,000 8,759,000 
          three months ended september 30,
                                                                                            
          2001:
                                                                                            
          proceeds from issuance of treasury stock
                                                                                           37,127,000 
          three months ended june 30,