7Baggers

White Mountains Insurance Group Quarterly Balance Sheets Chart

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Annual
 

White Mountains Insurance Group Quarterly Balance Sheets Table

Quarterly
 | 
Annual
 
Unit: USD2025-03-31 2024-12-31 2024-09-30 2024-03-31 2023-12-31 2023-09-30 2023-03-31 2022-12-31 2022-09-30 2022-06-30 2022-03-31 2021-12-31 2021-03-31 2020-12-31 2020-09-30 2020-06-30 2019-09-30 2019-06-30 2019-03-31 2018-09-30 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 2014-09-30 2014-06-30 2014-03-31 2013-12-31 2013-09-30 2013-06-30 2013-03-31 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 2008-06-30 2008-03-31 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 2003-12-31 
                                                                      
  assets                                                                    
  p&c insurance and reinsurance                                                                    
  fixed maturity investments, at fair value1,582,100,000 1,565,100,000 1,461,200,000 946,900,000 1,012,300,000 932,200,000 924,800,000 909,900,000 874,400,000 884,400,000 873,800,000 934,100,000 857,000,000 859,500,000 831,800,000 821,700,000 794,500,000 762,900,000 737,600,000 677,700,000 622,100,000 1,490,000,000 1,566,900,000 4,175,400,000 4,250,200,000 4,131,500,000 4,362,800,000 2,613,200,000 2,639,700,000 2,602,200,000 4,874,500,000 4,771,900,000 4,785,500,000 5,008,000,000 4,988,700,000 5,030,500,000 4,914,000,000 4,931,900,000 4,854,400,000 4,912,400,000 5,248,700,000 5,411,300,000 6,221,900,000 5,287,700,000 5,558,900,000 6,417,000,000 6,379,900,000 6,085,400,000 5,568,600,000 5,828,300,000 6,101,200,000 5,936,200,000 5,929,800,000 5,630,500,000 6,160,100,000 6,846,400,000 6,842,600,000 7,436,700,000 7,524,900,000 7,179,900,000 7,911,500,000 7,089,200,000 7,303,600,000 7,265,500,000 7,582,700,000 7,594,200,000 7,760,400,000 6,248,100,000 
  common equity securities, at fair value420,900,000 425,400,000 435,600,000 409,900,000 400,600,000 384,900,000 340,400,000 334,600,000 286,400,000 278,600,000 290,100,000 251,100,000 118,600,000  140,700,000 567,200,000 629,700,000 709,200,000 905,000,000 1,043,500,000 945,600,000 774,400,000 827,900,000 601,000,000 474,300,000 425,000,000 407,500,000 443,000,000 1,113,900,000 482,100,000 713,800,000 786,900,000 986,100,000 1,206,100,000 1,174,600,000 1,156,800,000 1,110,700,000 1,029,500,000 1,073,200,000 1,004,800,000 919,200,000 868,700,000 755,000,000 669,800,000 703,800,000 756,600,000 710,000,000 636,000,000 556,300,000 577,100,000 458,500,000 307,600,000 262,200,000 318,800,000 1,393,400,000 1,620,600,000 1,520,700,000 1,471,300,000 1,402,700,000 1,245,200,000 1,212,600,000 1,042,000,000 1,147,000,000 1,107,000,000 967,800,000 1,000,100,000 1,024,400,000 513,600,000 
  short-term investments, at fair value625,200,000 601,400,000 579,100,000 835,300,000 70,600,000 80,100,000 65,900,000 65,900,000 62,300,000 55,300,000 36,500,000 32,400,000 45,300,000 60,400,000 56,100,000 54,700,000 57,100,000 34,800,000 31,800,000 35,900,000 88,000,000                                                
  other long-term investments586,800,000 547,800,000 544,800,000 485,000,000 440,900,000 416,600,000 393,900,000 373,600,000 329,700,000 330,000,000 334,500,000 326,200,000 234,700,000 400,600,000 325,500,000 315,600,000 219,300,000 142,200,000 497,600,000 289,700,000 253,100,000 229,600,000 226,500,000 331,700,000 323,300,000 351,400,000 329,200,000 321,800,000 315,800,000 294,600,000 390,100,000 402,600,000 320,900,000 313,000,000 302,300,000 288,900,000 300,000,000 303,300,000 295,200,000 307,100,000 292,500,000 306,700,000 301,300,000 328,800,000 333,300,000 343,400,000 376,100,000 429,700,000 404,000,000 382,600,000 341,300,000 377,500,000 405,400,000 395,100,000               
  total investments3,215,000,000 3,139,700,000 3,020,700,000 2,677,100,000 1,082,900,000 1,012,300,000 990,700,000 975,800,000 936,700,000 939,700,000 910,300,000 966,500,000 902,300,000 919,900,000 887,900,000 876,400,000 851,600,000 797,700,000 769,400,000 713,600,000 710,100,000 3,280,500,000 2,692,900,000 5,339,000,000 5,334,800,000 5,213,500,000 5,521,300,000 3,639,700,000 4,280,700,000 3,709,500,000 6,823,400,000 6,906,400,000 6,976,300,000 7,161,800,000 7,213,400,000 7,192,600,000 7,057,500,000 6,945,600,000 6,972,800,000 7,283,600,000 7,224,300,000 7,617,000,000 8,268,000,000 7,199,600,000 7,529,200,000 8,671,200,000 8,732,500,000 8,655,400,000 8,389,300,000 9,128,300,000 9,232,500,000 9,284,600,000 8,921,000,000 8,804,700,000 10,747,000,000 11,536,100,000 12,150,200,000 11,910,300,000 11,495,700,000 11,252,100,000 11,332,700,000 9,852,000,000 9,793,700,000 9,829,000,000 9,866,400,000 10,128,700,000 10,091,200,000 8,547,500,000 
  cash160,500,000 141,200,000 148,800,000 129,100,000 6,700,000 4,900,000 4,800,000 18,200,000 17,300,000 21,600,000 22,300,000 19,800,000 18,900,000 42,800,000 49,900,000 32,000,000 11,300,000 10,300,000 10,400,000 17,900,000 9,400,000 48,600,000 53,300,000 125,000,000 149,800,000 244,700,000 135,000,000 178,800,000 179,300,000 200,000,000 354,200,000 335,800,000 543,500,000 331,000,000 338,600,000 382,800,000 411,000,000 348,300,000 411,500,000 549,200,000 811,600,000 605,400,000 705,400,000 557,700,000 483,700,000 452,500,000 434,800,000 401,200,000 348,800,000 345,000,000 366,000,000 258,100,000 405,200,000 448,800,000 220,800,000 198,300,000 229,600,000 185,600,000 172,900,000 186,300,000 159,000,000 210,300,000 191,600,000 183,100,000 187,700,000 205,400,000 204,000,000 89,900,000 
  reinsurance recoverables920,400,000 589,000,000 748,000,000 695,000,000 442,000,000 538,400,000 570,600,000 536,100,000 550,900,000 398,700,000 412,700,000 448,400,000 449,000,000                                                        
  insurance premiums receivable1,272,600,000 768,600,000 993,000,000 1,001,500,000 5,500,000 5,500,000 6,300,000 6,600,000 6,600,000 6,900,000 6,900,000 6,900,000 6,900,000 6,900,000 7,200,000 7,300,000 6,700,000 6,600,000 6,500,000 6,300,000 5,200,000 4,500,000 2,800,000 227,500,000 229,900,000 264,600,000 240,400,000 234,300,000 223,300,000 273,300,000                                       
  deferred acquisition costs279,700,000 165,200,000 199,700,000 213,300,000 40,100,000 38,500,000 36,900,000 36,000,000 34,900,000 33,900,000 33,100,000 33,100,000 28,700,000 27,800,000 26,100,000 25,000,000 21,400,000 20,500,000 19,600,000 17,600,000 15,900,000 14,100,000 13,000,000 110,400,000 106,900,000 109,600,000 113,900,000 109,800,000 107,600,000 110,800,000 198,100,000 192,000,000 204,400,000 191,200,000 190,000,000 174,700,000 188,200,000 180,600,000 190,400,000 211,300,000 200,000,000 198,800,000 187,000,000 202,900,000 194,100,000 233,500,000 210,800,000 241,700,000 241,900,000 298,300,000 303,800,000 329,200,000 329,400,000 327,700,000 350,400,000 338,400,000 325,900,000 358,600,000 351,600,000 338,600,000 320,300,000 333,500,000 324,900,000 312,200,000 288,400,000 308,300,000 313,000,000 233,600,000 
  goodwill and other intangible assets292,500,000 292,500,000 292,500,000 292,500,000 292,500,000 292,500,000 292,500,000 292,500,000 292,500,000 292,500,000 292,500,000 292,500,000 292,500,000 736,800,000 730,300,000 728,600,000 630,600,000 636,800,000 488,700,000 431,000,000 50,800,000 37,800,000 49,500,000 53,000,000  59,300,000                                           
  other assets184,800,000 202,800,000 175,800,000 140,900,000 36,800,000 22,200,000 21,600,000 21,900,000 22,300,000 19,700,000 18,400,000 18,500,000 14,800,000 15,400,000 15,000,000 14,600,000 16,400,000 16,100,000 17,100,000 5,100,000 5,100,000 46,100,000 62,800,000 254,300,000 274,600,000 226,300,000 239,400,000 286,900,000 318,700,000 307,700,000 322,700,000 323,600,000 466,700,000 520,100,000 537,700,000 458,100,000 397,300,000 483,300,000 416,500,000 626,500,000 673,000,000 580,900,000 681,900,000 760,200,000 679,300,000 744,400,000 779,400,000 694,900,000 705,000,000 648,500,000 691,500,000 767,500,000 791,400,000 760,100,000 735,300,000 726,600,000 605,000,000 593,100,000 640,800,000 628,800,000 645,100,000 555,500,000 554,400,000 540,100,000 526,500,000 506,600,000 574,800,000 682,200,000 
  total p&c insurance and reinsurance assets6,325,500,000 5,299,000,000 5,578,500,000 5,149,400,000 4,378,600,000 4,414,200,000 4,238,400,000 3,486,200,000 3,606,700,000 3,615,400,000 3,435,200,000 3,027,000,000 2,840,200,000                                                        
  financial guarantee                                                                    
  bam surplus notes, at fair value389,200,000 381,700,000 411,100,000                                                                  
  total financial guarantee assets1,203,100,000 1,179,400,000 1,201,900,000 1,158,600,000 1,172,000,000 1,083,400,000 1,060,300,000 1,058,500,000 1,017,800,000 1,021,800,000 991,000,000 1,044,800,000 976,800,000 1,017,800,000 991,300,000 960,500,000 912,900,000 864,500,000 834,500,000 765,500,000 750,100,000                                                
  asset management                                                                    
  accrued investment income23,500,000 18,000,000 15,700,000 22,100,000 17,600,000 15,800,000 19,100,000 12,400,000 12,500,000 11,200,000 11,800,000 16,900,000 5,200,000 5,000,000 5,200,000 5,200,000 5,500,000 5,300,000 5,400,000 4,800,000 4,400,000 15,400,000 16,000,000 27,200,000 26,100,000 18,900,000 16,000,000 13,400,000 14,000,000 13,700,000 33,700,000 30,400,000 32,700,000 43,600,000 37,000,000 39,300,000 33,700,000 45,900,000 44,700,000 45,500,000 54,100,000 52,000,000 51,400,000 58,300,000 61,900,000 66,300,000 66,900,000 61,600,000 60,600,000 59,400,000 67,400,000 70,500,000 69,900,000 64,500,000 80,000,000 78,000,000 78,600,000 89,100,000 85,800,000 84,700,000 87,400,000        
  total asset management assets1,223,300,000 1,108,400,000 1,094,100,000 953,100,000 959,400,000 835,900,000 768,000,000 825,900,000 920,700,000 881,400,000 747,500,000 727,100,000 457,700,000 430,200,000 351,900,000 339,300,000                                                     
  p&c insurance distribution                                                                    
  premiums, commissions and fees receivable67,400,000 70,000,000 72,700,000 43,300,000                                                                 
  total p&c insurance distribution assets615,000,000 584,600,000 599,600,000 528,100,000                                                                 
  other operations                                                                    
  investment in mediaalpha, at fair value165,000,000 201,600,000 323,400,000 465,600,000 254,900,000 188,800,000 253,800,000 168,600,000 148,200,000 166,900,000 280,400,000 261,600,000 600,200,000 802,200,000                                                       
  total other operations assets1,638,000,000 1,754,200,000 1,863,400,000 1,801,100,000 1,875,900,000 1,809,300,000 1,892,400,000 2,018,700,000 1,999,800,000 2,142,300,000 1,206,900,000 1,224,500,000 1,663,300,000 2,383,800,000 2,060,000,000 1,699,600,000 1,854,400,000 1,876,200,000 2,134,100,000                                                  
  total assets11,004,900,000 9,925,600,000 10,337,500,000 9,590,300,000 8,385,900,000 8,142,800,000 7,959,100,000 7,389,300,000 7,545,000,000 7,660,900,000 7,356,700,000 7,000,700,000 6,900,700,000 4,831,400,000 4,383,400,000 4,000,300,000 3,836,300,000 3,752,200,000 3,629,700,000 3,422,800,000 3,587,000,000 3,637,100,000 6,786,200,000 6,516,900,000 6,544,700,000 6,683,300,000 7,065,600,000 10,391,800,000 10,284,500,000 10,346,000,000 10,429,300,000 10,507,800,000 12,188,300,000 12,357,900,000 12,416,400,000 12,144,300,000 12,307,500,000 12,283,700,000 12,611,500,000 13,468,800,000 13,280,500,000 13,378,600,000 14,064,000,000 14,581,700,000 14,202,500,000 14,597,400,000 14,534,100,000 14,993,900,000 15,502,700,000 15,822,800,000 15,443,200,000 15,675,800,000 15,551,000,000 15,640,500,000 17,764,400,000 18,703,800,000 19,364,800,000 19,718,700,000 19,184,300,000 19,278,200,000 19,443,700,000 18,712,100,000 18,728,000,000 19,081,400,000 19,418,100,000 19,795,800,000 19,184,700,000 14,971,000,000 
  millions, except share and per share amounts 2,024,000,000   2,023,000,000   2,022,000,000    2,021,000,000  2,020,000,000                                                       
  liabilities                                                                    
  loss and loss adjustment expense reserves2,253,900,000 2,127,500,000 2,133,000,000 1,744,500,000 1,605,100,000 1,571,800,000 1,345,600,000 1,296,500,000 1,329,400,000 1,022,100,000 999,600,000 894,700,000 751,900,000           1,368,800,000 1,365,600,000 1,362,000,000 1,376,600,000 1,349,600,000 1,395,800,000 1,433,300,000 3,031,800,000 3,035,000,000 3,022,900,000 3,053,300,000 3,048,400,000 3,079,300,000 3,108,100,000 3,057,900,000 3,100,600,000 3,059,800,000 5,329,800,000 5,510,800,000 5,702,300,000 5,882,000,000 5,642,400,000 6,212,300,000 6,187,200,000 6,415,900,000 6,643,300,000 7,091,000,000 6,802,100,000 6,953,600,000 6,999,800,000 7,260,100,000 7,936,800,000 7,946,400,000 8,038,000,000 8,249,300,000 8,364,700,000 8,636,000,000 8,777,200,000 9,114,200,000 9,775,300,000 9,987,000,000 10,231,200,000 10,102,600,000 9,535,800,000 7,728,200,000 
  unearned insurance premiums1,500,600,000 853,300,000 1,149,800,000 1,234,700,000 325,800,000 312,300,000 299,800,000 298,300,000 286,700,000 274,000,000 267,300,000 266,300,000 243,700,000 237,500,000 226,900,000 218,600,000 203,500,000 187,800,000 179,600,000 156,200,000 140,200,000 118,500,000 109,900,000 678,100,000 658,000,000 674,100,000 619,700,000 626,500,000 612,600,000 671,300,000                                       
  debt156,100,000 154,500,000 156,800,000 155,400,000 146,900,000 146,800,000 146,600,000 146,500,000 146,400,000 146,300,000 184,800,000 185,900,000 44,100,000 272,600,000 270,200,000 268,400,000 219,400,000 219,700,000 184,500,000 149,300,000 21,500,000 9,400,000 10,600,000 284,700,000 285,900,000 288,500,000 289,800,000 532,600,000 442,400,000 383,300,000 748,500,000 749,800,000 678,100,000 677,500,000 677,600,000 676,400,000 676,300,000 676,300,000 676,200,000 676,600,000 677,600,000 677,200,000 671,200,000 669,000,000 669,000,000 818,800,000 818,800,000 818,700,000 851,700,000 1,026,100,000 1,050,700,000 1,050,500,000 1,271,400,000 1,349,200,000 1,367,100,000 1,520,600,000 1,666,000,000 1,192,800,000 1,183,600,000 1,183,600,000 1,106,700,000 794,200,000 838,200,000 779,100,000 779,100,000 775,200,000 777,600,000 743,000,000 
  reinsurance payable385,800,000 149,500,000 230,200,000 262,500,000 81,100,000 146,300,000 193,000,000 251,100,000 312,700,000 418,800,000 348,900,000 424,100,000 487,500,000                                                        
  contingent consideration165,000,000 155,300,000 141,500,000 94,000,000 94,000,000 62,100,000 42,900,000 45,300,000 32,900,000 30,200,000 30,100,000 28,000,000                                                         
  other liabilities196,700,000 224,700,000 188,900,000 190,100,000 31,800,000 40,000,000 30,100,000 29,000,000 29,500,000 32,700,000 28,300,000 30,900,000 28,600,000 28,300,000 27,800,000 27,300,000 27,400,000 27,400,000 28,100,000 30,000,000 12,200,000 45,400,000 44,900,000 178,500,000 199,900,000 210,900,000 188,500,000 229,800,000 264,700,000 304,900,000 297,300,000 338,500,000 355,400,000 336,800,000 343,300,000 362,900,000 362,700,000 371,500,000 374,400,000 461,800,000 461,900,000 441,400,000 534,100,000 1,310,600,000 1,089,100,000 1,142,800,000 1,245,900,000 1,119,900,000 1,104,800,000 928,100,000 990,000,000 972,100,000 931,700,000 1,031,300,000 904,500,000 820,300,000 864,600,000 901,500,000 775,600,000 825,900,000 913,700,000 1,178,500,000 1,003,200,000 992,900,000 1,165,500,000 1,200,700,000 1,205,500,000 1,333,200,000 
  total p&c insurance and reinsurance liabilities4,658,100,000 3,664,800,000 4,000,200,000 3,681,200,000 2,876,100,000 3,081,400,000 3,033,300,000 2,520,900,000 2,743,900,000 2,780,300,000 2,554,900,000 2,122,400,000 2,006,800,000                                                        
  total financial guarantee liabilities463,300,000 464,100,000 453,900,000 519,300,000 531,700,000 519,000,000 488,600,000 501,800,000 484,200,000 469,500,000 306,800,000 321,900,000 283,300,000 291,500,000 280,500,000 263,000,000 253,500,000 229,700,000 219,400,000 192,700,000 179,600,000                                                
  total asset management liabilities330,600,000 316,700,000 294,400,000 265,600,000 275,400,000 257,300,000 246,400,000 273,300,000 313,200,000 298,600,000 260,500,000 261,000,000 111,300,000 96,300,000 81,200,000 77,300,000                                                     
  premiums and commissions payable86,200,000 88,100,000 93,700,000 61,700,000                                                                 
  total p&c insurance distribution liabilities282,700,000 167,700,000 172,000,000 118,300,000                                                                 
  accrued incentive compensation28,200,000 79,300,000 64,500,000 11,900,000 27,200,000 19,900,000 12,100,000 28,000,000 21,600,000 16,500,000 11,200,000 24,700,000 11,000,000 25,700,000 19,400,000 14,100,000 19,000,000 14,500,000 10,100,000 40,300,000 8,400,000 76,900,000 63,300,000 83,200,000 140,000,000 124,200,000 106,300,000 114,200,000 141,700,000 121,000,000 124,900,000 100,500,000 187,500,000 157,900,000 124,900,000 218,300,000 161,600,000 125,900,000 100,800,000 144,700,000 113,600,000 90,000,000 187,900,000 169,900,000 153,300,000 122,500,000 176,500,000 150,900,000 132,600,000 116,400,000 204,900,000 153,600,000                 
  total other operations liabilities130,500,000 181,300,000 157,200,000 115,300,000 141,100,000 120,900,000 98,000,000 158,300,000 137,400,000 620,500,000 71,200,000 95,400,000 83,300,000 133,900,000 236,100,000 95,800,000 105,800,000 85,700,000 80,500,000                                                  
  total liabilities5,865,200,000 4,794,600,000 5,077,700,000 4,699,700,000 3,824,300,000 3,978,600,000 3,866,300,000 3,454,300,000 3,678,700,000 4,168,900,000 3,687,400,000 3,296,000,000 2,964,800,000 1,013,500,000 1,074,200,000 937,000,000 765,400,000 744,300,000 651,400,000 583,200,000 291,200,000 299,900,000 3,022,100,000 2,759,300,000 2,807,500,000 2,881,900,000 2,966,200,000 6,154,500,000 5,916,500,000 6,139,700,000 5,970,800,000 5,968,000,000 7,689,500,000 7,749,300,000 7,888,500,000 7,746,900,000 8,020,300,000 8,093,300,000 8,329,500,000 9,090,400,000 8,946,000,000 9,069,100,000 9,396,100,000 10,562,600,000 9,986,700,000 10,388,300,000 10,273,300,000 10,722,300,000 11,342,300,000 11,567,900,000 11,101,700,000 11,428,100,000 11,699,600,000 12,158,200,000 13,024,000,000 13,357,800,000 13,931,100,000 14,097,300,000 13,721,400,000 14,106,500,000 14,385,200,000 14,593,400,000 14,863,700,000 15,209,200,000 15,584,900,000 15,913,000,000 15,092,900,000 11,991,800,000 
  equity                                                                    
  white mountains’s common shareholders’ equity                                                                    
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 2,573,726 and 2,568,148 shares2,600,000                                                                    
  paid-in surplus564,500,000 563,800,000 560,700,000 551,900,000 548,700,000 544,900,000 535,200,000 536,000,000 532,700,000 600,300,000 583,300,000 585,900,000 594,800,000 592,100,000   590,000,000 587,300,000 582,600,000 576,300,000 671,500,000 665,600,000 810,500,000 802,500,000 806,100,000 805,200,000 868,100,000 933,500,000 972,600,000 992,300,000 1,025,200,000 1,032,700,000 1,030,900,000 1,047,700,000 1,046,700,000 1,044,900,000 1,040,400,000 1,036,200,000 1,031,100,000 1,095,600,000 1,102,200,000 1,099,500,000 1,253,700,000 1,262,700,000 1,313,500,000 1,312,600,000 1,350,800,000 1,370,800,000 1,397,600,000 1,423,500,000 1,436,100,000 1,431,600,000 1,427,300,000 1,422,800,000 1,676,700,000 1,691,100,000 1,690,600,000 1,723,900,000 1,721,100,000 1,716,600,000 1,716,700,000 1,715,900,000 1,715,600,000 1,715,200,000 1,716,400,000 1,718,500,000 1,719,500,000 1,399,600,000 
  retained earnings3,943,000,000 3,919,000,000 4,048,300,000 3,917,700,000 3,690,800,000 3,404,300,000 3,367,300,000 3,211,800,000 3,175,900,000 2,725,100,000 2,956,200,000 2,957,500,000 3,226,700,000 3,311,200,000 2,822,100,000 2,589,300,000 2,611,500,000 2,562,800,000 2,542,300,000 2,407,300,000 2,765,000,000 2,800,800,000 2,835,200,000 2,821,800,000 2,797,200,000 2,846,700,000 3,006,600,000 2,959,600,000 3,084,900,000 2,888,300,000 3,069,200,000 3,080,800,000 2,961,500,000 2,965,800,000 2,880,800,000 2,802,300,000 2,684,400,000 2,627,200,000 2,601,400,000 2,577,400,000 2,576,300,000 2,553,700,000 2,789,700,000 2,004,000,000 2,102,000,000 2,094,200,000 2,175,600,000 2,125,900,000 2,108,700,000 2,148,200,000 2,215,900,000 2,116,200,000 1,956,600,000 1,776,300,000 2,495,400,000 2,802,200,000 2,837,600,000 2,737,300,000 2,647,500,000 2,566,700,000 2,496,000,000 2,218,200,000 2,077,700,000 1,983,400,000 1,899,800,000 1,888,000,000 1,975,900,000 1,286,400,000 
  accumulated other comprehensive income, after-tax:                                                                    
  net unrealized gains from foreign currency translation-500,000 -1,700,000 -1,000,000 -1,800,000                                                                 
  total white mountains’s common shareholders’ equity4,509,600,000 4,483,700,000 4,610,600,000 4,470,400,000 4,240,500,000 3,949,100,000 3,902,400,000 3,746,900,000 3,708,000,000 3,323,300,000 3,542,100,000 3,548,100,000 3,825,900,000 3,906,000,000 3,407,700,000 3,166,000,000 3,193,400,000 3,144,300,000 3,122,000,000 2,984,000,000 3,439,000,000 3,468,800,000 3,647,300,000 3,625,200,000 3,603,300,000 3,652,200,000 3,875,200,000 3,785,900,000 3,913,200,000 3,745,500,000 3,974,600,000 4,011,300,000 4,010,100,000 4,105,500,000 4,014,500,000                                  
  noncontrolling interests630,100,000 647,300,000 649,200,000 420,200,000 321,100,000 215,100,000 190,400,000                                                              
  total equity5,139,700,000 5,131,000,000 5,259,800,000 4,890,600,000 4,561,600,000 4,164,200,000 4,092,800,000 3,935,000,000 3,866,300,000 3,492,000,000 3,669,300,000 3,704,700,000 3,935,900,000 3,817,900,000 3,309,200,000 3,063,300,000 3,070,900,000 3,007,900,000 2,978,300,000 2,839,600,000 3,295,800,000 3,337,200,000 3,764,100,000 3,757,600,000 3,737,200,000 3,801,400,000 4,099,400,000 4,237,300,000 4,368,000,000 4,206,300,000 4,458,500,000 4,539,800,000 4,498,800,000 4,608,600,000 4,527,900,000 4,397,400,000 4,287,200,000 4,190,400,000 4,282,000,000 4,378,400,000 4,334,500,000 4,309,500,000 4,667,900,000 4,019,100,000 4,215,800,000 4,209,100,000 4,260,800,000 4,271,600,000 4,160,400,000 4,254,900,000 4,341,500,000 4,247,700,000 3,851,400,000 3,482,300,000               
  total liabilities and equity11,004,900,000 9,925,600,000 10,337,500,000 9,590,300,000 8,385,900,000 8,142,800,000 7,959,100,000 7,389,300,000 7,545,000,000 7,660,900,000 7,356,700,000 7,000,700,000 6,900,700,000 4,831,400,000 4,383,400,000 4,000,300,000 3,836,300,000 3,752,200,000 3,629,700,000 3,422,800,000 3,587,000,000 3,637,100,000 6,786,200,000 6,516,900,000 6,544,700,000 6,683,300,000 7,065,600,000 10,391,800,000 10,284,500,000 10,346,000,000 10,429,300,000 10,507,800,000 12,188,300,000 12,357,900,000 12,416,400,000 12,144,300,000 12,307,500,000 12,283,700,000 12,611,500,000 13,468,800,000 13,280,500,000 13,378,600,000 14,064,000,000 14,581,700,000 14,202,500,000 14,597,400,000 14,534,100,000 14,993,900,000 15,502,700,000 15,822,800,000 15,443,200,000 15,675,800,000 15,551,000,000 15,640,500,000               
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 2,568,148 and 2,560,452 shares 2,600,000 2,600,000                                                                  
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 2,565,733 and 2,560,452 shares   2,600,000                                                                 
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 2,560,452 and 2,572,156 shares    2,600,000 2,600,000                                                               
  net unrealized gains from foreign currency translation and interest rate swap    -1,600,000 -2,700,000 -2,700,000 -3,500,000 -3,200,000 -5,000,000 -400,000                                                          
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 2,564,484 and 2,572,156 shares      2,600,000                                                              
  ceded unearned premiums       59,200,000 59,700,000 105,400,000 86,800,000 67,100,000 145,500,000                                      111,100,000 128,600,000 159,200,000 165,700,000 134,300,000 158,800,000 171,900,000 129,200,000 130,900,000 133,600,000 87,900,000 113,700,000 167,100,000 214,200,000 200,700,000 242,200,000 241,900,000 185,300,000 
  deferred acquisition costs and value of in-force business acquired       127,200,000 151,400,000 192,400,000 179,800,000 108,200,000                                                         
  assets held for sale - nsm group         997,800,000                                                           
  assets held for sale - other                                                                    
  liabilities held for sale - nsm group         504,400,000                                                           
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 2,572,156 and 3,017,772 shares       2,600,000                                                             
  accumulated other comprehensive gain, after-tax:                                                                    
  non-controlling interests       188,100,000 158,300,000 168,700,000 127,200,000 156,600,000 110,000,000 -88,100,000 -98,500,000 -102,700,000 -122,500,000 -136,400,000 -143,700,000 -144,400,000 -143,200,000 -131,600,000 116,800,000 132,400,000 133,900,000 149,200,000 224,200,000 451,400,000 454,800,000                                        
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 2,576,232 and 3,017,772 shares        2,600,000                                                            
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 2,942,877 and 3,017,772 shares         2,900,000                                                           
  specialty insurance distribution                                                                    
  premiums and commissions receivable          97,600,000  77,000,000  67,700,000 76,700,000                                                     
  total specialty insurance distribution assets          976,100,000 977,300,000 962,700,000 999,600,000 980,200,000 1,000,900,000 826,700,000 851,100,000 661,100,000 540,400,000                                                 
  assets held for sale          15,900,000 16,100,000 700,000 2,300,000 700,000 3,000,000 2,800,000 2,800,000 3,300,000 3,300,000 3,300,000  3,696,400,000  10,100,000 27,000,000 384,600,000 5,215,500,000 4,407,000,000 4,528,100,000  58,000,000 1,699,200,000 1,750,700,000 1,803,100,000 1,880,100,000 1,957,200,000 2,047,000,000 2,155,200,000 2,388,200,000   132,600,000 1,399,500,000 1,213,900,000                        
  premiums payable          146,000,000 135,900,000 116,000,000 113,400,000 116,900,000 139,700,000 92,600,000 118,700,000 93,400,000 56,600,000                                                 
  total specialty insurance distribution liabilities          494,000,000 495,300,000 480,100,000 491,800,000 476,400,000 500,900,000 400,800,000 425,400,000 351,500,000 253,700,000                                                 
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 2,994,162 and 3,017,772 shares          3,000,000                                                          
  premium and commission receivable           85,000,000  76,700,000   53,600,000 57,600,000 51,900,000 29,100,000                                                 
  cash pre-funded/placed in escrow for ark transaction             646,300,000                                                       
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 3,017,772 and 3,102,011 shares           3,000,000                                                         
  net unrealized foreign currency translation and interest rate swap gains           1,700,000 1,300,000                                                        
  deferred acquisition cost            79,200,000                                                        
  value of in-force business acquired            42,900,000                                                        
  accounts receivable on unsettled investment sales            3,500,000    300,000 8,000,000 6,100,000 200,000  190,100,000 199,500,000 24,500,000 6,200,000 179,000,000 21,500,000 4,500,000 41,900,000 11,500,000 23,300,000 12,000,000 39,000,000 76,600,000 19,900,000 12,100,000 38,200,000 14,000,000 99,000,000 167,200,000 76,200,000 6,500,000 4,700,000 20,300,000 23,400,000 49,900,000 40,000,000 147,400,000 87,100,000 112,300,000 27,600,000 47,000,000 10,300,000 25,600,000 27,000,000 36,500,000 35,300,000 21,700,000 24,300,000 40,200,000 8,500,000 354,100,000 23,600,000 45,700,000 21,700,000 27,000,000 19,500,000 9,100,000 
  contingent consideration related to the ark transaction            22,500,000                                                        
  accounts payable on unsettled investment purchases            61,600,000  6,400,000 3,000,000 3,600,000  1,600,000 6,500,000 18,800,000 49,700,000 114,600,000 17,300,000  30,000,000 69,900,000 6,900,000  46,000,000 57,700,000 92,600,000 76,000,000 28,200,000 80,900,000 20,500,000 28,100,000 55,700,000 25,700,000 47,700,000 44,500,000 103,500,000 34,600,000 57,100,000 44,900,000 99,000,000 22,400,000 110,000,000 51,800,000 37,100,000 9,100,000 60,200,000 64,400,000 23,500,000 17,400,000 72,800,000 106,300,000 85,400,000 32,000,000 19,700,000 66,800,000 303,500,000 63,700,000 165,700,000 43,400,000 162,800,000 95,700,000 371,600,000 
  contingent consideration earnout liabilities            7,900,000 14,600,000 11,800,000 11,700,000 28,700,000 30,900,000 27,500,000 20,100,000                                                 
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 3,107,267 and 3,102,011 shares and paid-in surplus            3,100,000                                                        
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 3,102,011 and 3,185,353 shares             3,100,000                                                       
  accumulated other comprehensive loss, after-tax:                                                                    
  net unrealized losses from foreign currency translation and interest rate swap             -400,000                                                       
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 3,102,011 and 3,185,353 shares and paid-in surplus              592,100,000                                                      
  net unrealized foreign currency translation and interest rate swap losses              -6,500,000 -10,300,000 -11,300,000                                                    
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 3,101,761 and 3,185,353 shares and paid-in surplus               587,000,000                                                     
  global asset and wealth management                                                                    
  total global asset and wealth management assets                242,300,000 160,400,000                                                   
  marketing technology                                                                    
  accounts receivable from publishers and advertisers                   35,900,000 35,400,000                                                
  total marketing technology assets                   97,000,000 103,700,000                                                
  total global asset and wealth management liabilities                5,300,000 3,500,000                                                   
  amounts due to publishers and advertisers                   37,700,000 37,400,000                                                
  total marketing technology liabilities                   56,600,000 60,700,000                                                
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 3,185,353 and 3,173,115 shares                3,200,000 3,200,000                                                   
  net unrealized foreign currency translation losses and interest rate swap                 -9,000,000 -6,100,000 -2,800,000                                                 
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 3,181,199 and 3,173,115 shares                  3,200,000                                                  
  other                                                            600,000        
  total other assets                   2,019,900,000 2,733,200,000                                                
  total other liabilities                   80,200,000 50,900,000                                                
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 3,180,540 and 3,750,171 shares                   3,200,000                                                 
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 3,753,405 and 3,750,171 shares                    3,800,000                                                
  net unrealized foreign currency translation losses                    -1,300,000 -1,300,000  -600,000 -1,400,000 -600,000 -700,000 -108,300,000 -145,600,000 -142,400,000 -123,700,000 -167,600,000                               9,300,000      
  short-term investments, at amortized cost                     786,500,000 71,600,000 230,900,000 287,000,000 305,600,000 421,800,000 261,700,000 211,300,000 325,000,000 840,500,000 929,200,000 834,900,000 564,000,000 674,000,000 635,900,000 648,000,000 606,800,000 654,400,000 917,300,000 618,400,000 877,500,000 846,000,000 772,800,000 813,500,000 998,200,000 1,106,300,000 1,348,300,000 1,663,700,000 2,102,200,000 2,098,400,000 2,336,600,000 2,023,300,000 2,148,400,000 2,256,600,000 1,988,000,000 2,372,200,000 1,614,800,000 1,152,900,000 1,473,600,000 1,344,900,000 1,222,800,000 873,500,000 949,700,000 727,800,000 1,027,300,000 773,100,000 1,546,600,000 
  liabilities held for sale                      2,678,800,000  5,100,000 7,800,000 150,600,000 3,121,100,000 2,884,000,000 3,032,800,000   1,699,200,000 1,750,700,000 1,803,100,000 1,880,100,000 1,957,200,000 2,047,000,000 2,155,200,000 2,388,200,000   107,600,000 909,400,000 779,900,000                        
  white mountains’s common shares at 1 par value per share - authorized 50,000,000 shares;                                                                    
  issued and outstanding 3,749,971 and 4,563,814 shares                     3,700,000                                               
  accumulated other comprehensive loss, after tax:                                                                    
  accumulated other comprehensive income from net change in benefit plan assets and obligations                      -3,000,000                                              
  issued and outstanding 4,571,625 and 4,563,814 shares                      4,600,000                                              
  reinsurance recoverable on unpaid losses                       174,700,000 172,900,000 169,400,000 162,800,000 150,900,000 186,500,000 214,600,000 427,500,000 436,900,000 430,700,000 433,200,000 425,200,000 428,100,000 416,000,000 388,600,000 410,800,000 356,800,000 2,369,400,000 2,465,400,000 2,507,300,000 2,581,200,000 2,193,100,000 2,338,600,000 1,064,900,000 2,621,400,000 2,778,600,000 2,919,600,000 1,217,600,000 1,230,600,000 1,201,100,000 1,329,200,000 1,501,800,000 1,622,200,000 1,635,300,000 1,789,300,000 1,864,300,000 2,006,400,000 2,134,500,000 2,348,000,000 2,725,300,000 2,892,000,000 3,003,600,000 2,765,200,000 2,325,700,000 1,213,500,000 
  reinsurance recoverable on paid losses                       3,400,000 6,600,000 16,400,000 20,700,000 16,600,000 7,500,000 22,600,000 31,700,000 29,800,000 27,200,000 18,900,000 15,200,000 25,400,000 18,800,000 16,100,000 15,600,000 14,800,000 39,700,000 39,100,000 30,500,000 30,900,000 44,500,000 31,900,000 64,400,000 31,900,000 36,800,000 49,700,000 35,000,000 41,000,000 42,900,000 66,900,000 50,800,000 41,200,000 88,200,000 58,100,000 57,700,000 131,900,000 159,400,000 89,300,000 116,000,000 96,100,000 77,000,000 103,300,000 116,300,000 121,700,000 
  deferred tax asset                       125,500,000 126,700,000 119,500,000 122,200,000 133,600,000 112,800,000 133,900,000 440,200,000 417,900,000 439,100,000 462,800,000 484,900,000 512,100,000 555,500,000 540,500,000 539,100,000 555,000,000 504,600,000 524,700,000 536,900,000 431,700,000 407,400,000 480,600,000 499,700,000 483,500,000 567,300,000 551,100,000 564,000,000 512,600,000 567,500,000 658,100,000 484,900,000 324,100,000 253,500,000 238,700,000 222,400,000 242,600,000 276,000,000 288,900,000 324,200,000 317,700,000 341,200,000 338,300,000 310,900,000 260,000,000 
  ceded unearned insurance premiums                       52,400,000 44,200,000 35,100,000 34,500,000 36,300,000 29,500,000 41,400,000                                       
  funds held under insurance contracts                       148,700,000 153,000,000 156,200,000 140,900,000 134,900,000 137,800,000 100,300,000                                       
  issued and outstanding 4,572,792 and 4,563,814 shares                       4,600,000                                             
  pension liability                       -3,100,000                                             
  goodwill and intangible assets                        55,900,000  53,300,000 371,500,000 375,700,000 381,700,000 355,600,000 362,600,000                                     
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 4,563,814 and 5,623,735 shares                        4,600,000                                            
  pension liability and other                        -3,200,000 -3,700,000 -3,800,000 -4,300,000 -4,300,000 -3,900,000 -4,100,000 -4,400,000 4,500,000 4,300,000 4,200,000 4,100,000 -11,000,000 -11,300,000 -11,500,000 -10,400,000 -9,100,000                            
  ceded reinsurance payable                         28,200,000 23,900,000 31,800,000 30,500,000 46,800,000 189,600,000 151,800,000 134,000,000 159,200,000 157,900,000 71,900,000 153,600,000 156,900,000 175,700,000 138,600,000 175,600,000 194,000,000 134,600,000 188,300,000 160,600,000 224,800,000 221,000,000 293,300,000 268,800,000 227,300,000 92,000,000 152,100,000 158,600,000 162,600,000 100,400,000 88,400,000 124,600,000 124,000,000 125,400,000 141,000,000 138,400,000 135,600,000 166,900,000 173,700,000 204,500,000 219,100,000 202,600,000  
  issued and outstanding 4,578,698 and 5,623,735 shares                         4,600,000                                           
  issued and outstanding 4,963,921 and 5,623,735 shares                          5,000,000                                          
  deferred tax liability                           7,100,000 7,000,000  264,800,000 254,000,000 303,000,000 336,500,000 353,900,000 356,200,000 329,600,000 317,500,000 337,100,000 399,700,000 368,100,000 384,100,000 365,500,000 360,600,000 374,200,000 369,200,000 373,200,000 368,100,000 320,900,000 339,600,000 355,300,000 343,600,000 309,400,000 289,500,000 369,200,000 453,800,000 390,200,000 327,200,000 312,000,000 311,100,000 311,500,000 241,100,000 241,000,000 277,500,000 274,300,000 281,700,000 281,300,000  
  issued and outstanding 5,415,462 and 5,623,735 shares                           5,400,000                                         
  investments in unconsolidated affiliates                             392,600,000 397,200,000 450,800,000 413,500,000 419,100,000 373,300,000 321,400,000 331,700,000 331,900,000 383,600,000 376,300,000 337,500,000 294,900,000 275,300,000 458,600,000 422,900,000 394,900,000 389,700,000 440,000,000 410,000,000 365,800,000 344,800,000 356,100,000 209,000,000 99,700,000 195,000,000 289,000,000 362,300,000 404,400,000 381,000,000          
  white mountains’s common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 5,623,735 and 5,986,214 shares                            5,600,000                                        
  equity in net unrealized gains from investments in symetra common shares                                19,100,000 29,000,000  -40,400,000                                 
  convertible fixed maturity and preferred investments, at fair value                             5,600,000 4,500,000 15,800,000                                     
  funds held by ceding entities                             4,600,000 137,400,000 99,600,000 123,900,000                                    
  issued and outstanding 5,745,002 and 5,986,214 shares                             5,700,000                                       
  accumulated other comprehensive income, after tax:                                                                    
  equity in net unrealized gains from investment in symetra common shares                             5,500,000 2,000,000 63,800,000                                     
  non-controlling interest - onebeacon ltd.                             246,900,000 255,000,000 258,800,000 275,600,000 280,600,000 279,200,000  263,300,000 258,400,000 263,500,000                              
  non-controlling interest - sig preference shares                             250,000,000 250,000,000 250,000,000 250,000,000 250,000,000 250,000,000  250,000,000 250,000,000 250,000,000                              
  non-controlling interest - mutuals and reciprocals                             -149,400,000 -146,200,000 -140,500,000                                     
  non-controlling interest - other                             113,300,000 125,100,000 160,200,000 59,400,000 61,500,000 68,500,000  48,000,000 47,900,000 46,800,000                              
  total non-controlling interests                             460,800,000 483,900,000 528,500,000 488,700,000 503,100,000 513,400,000 491,900,000 497,200,000 501,200,000 523,100,000                              
  insurance and reinsurance premiums receivable                              711,900,000 706,900,000 677,800,000 717,900,000 734,800,000 518,900,000 684,900,000 706,700,000 717,600,000 678,100,000 747,000,000 737,300,000 489,200,000 644,800,000 672,000,000 838,200,000 635,400,000 842,200,000 861,400,000 1,004,500,000 785,500,000 922,700,000 986,500,000 982,600,000 929,000,000 953,300,000 976,200,000 971,100,000 1,007,300,000 1,007,400,000 913,600,000 1,002,300,000 1,062,400,000 1,099,200,000 1,014,300,000 1,039,700,000 981,900,000 779,000,000 
  ceded unearned insurance and reinsurance premiums                              172,400,000 145,100,000 114,300,000 142,000,000 149,500,000 92,400,000 116,400,000 137,000,000 144,100,000 113,600,000 135,200,000 145,500,000 87,300,000 104,400,000 141,300,000 188,800,000 184,700,000 252,300,000 249,300,000 236,400,000                   
  unearned insurance and reinsurance premiums                              1,110,800,000 1,102,500,000 1,089,500,000 1,093,400,000 1,116,600,000 901,400,000 1,010,300,000 1,015,000,000 1,064,900,000 1,067,100,000 1,065,400,000 1,074,400,000 846,900,000 976,400,000 1,033,800,000 1,314,400,000 1,140,300,000 1,361,600,000 1,385,700,000 1,698,600,000 1,498,500,000 1,655,400,000 1,704,400,000 1,732,300,000 1,743,600,000 1,760,300,000 1,753,800,000 1,743,200,000 1,735,700,000 1,746,600,000 1,584,900,000 1,714,900,000 1,730,700,000 1,742,400,000 1,582,000,000 1,717,900,000 1,759,000,000 1,409,400,000 
  funds held under insurance and reinsurance contracts                              145,400,000 143,300,000 132,200,000 124,000,000 127,800,000 127,100,000                                 
  issued and outstanding 5,960,542 and 5,986,214 shares                              6,000,000                                      
  issued and outstanding 5,991,584 and 5,986,214 shares                               6,000,000                                     
  convertible fixed maturity investments, at fair value                                48,900,000 70,700,000 73,800,000 80,500,000 84,800,000 74,100,000 95,600,000 142,000,000 145,500,000 152,800,000 143,800,000 140,500,000 119,700,000 156,000,000 160,200,000 156,000,000 196,700,000 238,100,000 233,100,000 326,700,000 300,300,000 265,000,000 353,000,000 414,600,000 463,000,000 529,500,000 544,700,000 485,800,000         
  variable annuity benefit guarantee                                11,700,000 31,800,000 54,100,000 52,800,000 143,700,000 194,100,000 251,600,000 672,400,000 661,800,000 548,500,000 768,500,000                          
  issued and outstanding 6,028,251 and 6,176,739 shares                                6,000,000                                    
  net unrealized foreign currency translation gains                                -11,900,000 52,500,000 80,500,000 88,400,000 93,500,000 47,200,000 82,000,000 80,800,000 39,500,000 69,400,000 46,100,000 35,700,000 117,600,000 123,200,000 61,400,000 57,400,000   11,500,000 29,700,000   28,700,000 162,300,000 170,000,000 79,100,000 52,800,000 35,900,000 37,200,000 11,500,000       
  non-controlling interest - hg global                                18,000,000 18,200,000 18,400,000  16,600,000 16,600,000 16,600,000                              
  non-controlling interest - bam                                -114,300,000 -107,200,000 -102,700,000  -80,700,000 -71,700,000 -53,800,000                              
  funds held by ceding companies                                 89,000,000 93,800,000 106,300,000 101,100,000 98,200,000 110,600,000 102,700,000 107,900,000 111,100,000 106,500,000 131,600,000 135,800,000 106,600,000 118,700,000 120,400,000 111,000,000 103,900,000 123,100,000 123,800,000 141,400,000 145,600,000 203,300,000 221,000,000 231,700,000 352,300,000 366,700,000 438,200,000 452,800,000 467,500,000 554,700,000 566,100,000 620,400,000 707,600,000 735,300,000  
  issued and outstanding 6,150,515 and 6,176,739 shares                                 6,200,000                                   
  issued and outstanding 6,174,386 and 6,176,739 shares                                  6,200,000                                  
  equity in net unrealized losses from investments in symetra common shares                                  -3,900,000                                  
  white mountains’ common shareholders’ equity                                                                    
  white mountains’ common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 6,176,739 and 6,290,964 shares                                   6,200,000                                 
  total white mountains’ common shareholders’ equity                                   3,905,500,000 3,790,000,000 3,689,200,000 3,758,900,000 3,809,300,000 3,742,500,000 3,718,800,000 4,087,700,000 3,444,700,000 3,620,500,000 3,595,200,000 3,653,000,000 3,667,800,000 3,513,600,000 3,598,300,000 3,657,400,000 3,577,300,000                 
  non-controlling interest — onebeacon ltd.                                   273,700,000                                 
  non-controlling interest — sig preference shares                                   250,000,000                                 
  non-controlling interest — hg global                                   16,600,000                                 
  non-controlling interest — bam                                   -97,600,000                                 
  non-controlling interest — consolidated limited partnerships and a.w.g. dewar                                   49,200,000                                 
  funds held under reinsurance treaties                                    89,100,000 75,500,000 67,300,000 33,800,000 47,700,000 45,200,000 42,900,000 39,300,000 39,500,000 84,500,000 88,000,000 83,900,000 80,400,000 103,700,000 97,400,000 85,300,000 55,900,000 76,600,000 75,100,000 76,000,000 98,700,000 99,500,000 110,400,000 126,400,000 141,600,000 119,600,000 130,100,000 131,500,000 171,400,000 169,900,000 170,400,000 211,900,000 
  white mountains’ common shares at 1 par value per share - authorized 50,000,000 shares;                                                                    
  issued and outstanding 6,176,739 and 6,290,964 shares                                    6,200,000                                
  equity in net unrealized gains from investments in unconsolidated affiliates                                    -23,500,000 -16,300,000 49,700,000 59,300,000 27,000,000                            
  issued and outstanding 6,176,489 and 6,290,964 shares                                     6,200,000                               
  issued and outstanding 6,176,210 and 6,290,964 shares                                      6,200,000                              
  issued and outstanding 6,583,653 and 7,577,855 shares                                       6,600,000                             
  noncontrolling interest - onebeacon ltd.                                       259,700,000 280,400,000 281,900,000  269,800,000 282,600,000 300,300,000  292,600,000 337,900,000 346,300,000  337,400,000 315,500,000 287,000,000               
  noncontrolling interest - sig preference shares                                       250,000,000 250,000,000 250,000,000                           
  noncontrolling interest - hg global                                       16,600,000                             
  noncontrolling interest - bam                                       -18,000,000                             
  noncontrolling interest - other                                       60,800,000 61,600,000 58,800,000                           
  total noncontrolling interests                                       569,100,000 592,000,000 590,700,000 580,200,000 574,400,000 595,300,000 613,900,000 607,800,000 603,800,000 646,800,000 656,600,000 684,100,000 670,400,000 647,300,000 616,100,000               
  issued and outstanding 6,630,318 and 7,577,855 shares                                        6,600,000                            
  issued and outstanding 6,638,873 and 7,577,855 shares                                         6,600,000                           
  equity in net unrealized losses from investments in unconsolidated affiliates                                                                    
  white mountains’ common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 7,577,855 and 8,194,925 shares                                          7,600,000                          
  equity in unrealized gains from investments in unconsolidated affiliates                                           135,700,000 80,600,000 58,500,000 58,500,000 111,400,000 74,300,000 23,800,000  5,600,000                 
  noncontrolling interest—onebeacon, ltd.                                          273,100,000    295,000,000    351,000,000                  
  noncontrolling interest—sig preference shares                                          250,000,000                          
  noncontrolling interest—consolidated limited partnerships and a.w.g dewar                                          57,100,000    62,800,000    83,100,000                  
  shareholders’ equity and noncontrolling interests                                                                    
  white mountains’ common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 7,630,717 and 8,194,925 shares                                           7,600,000                         
  noncontrolling interest - sirius group preference shares                                           250,000,000                         
  noncontrolling interest - consolidated limited partnerships and a.w.g dewar                                           54,600,000 62,700,000 63,600,000  61,200,000 58,900,000 60,300,000  83,000,000 81,800,000 79,100,000               
  white mountains’ common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 7,958,589 and 8,194,925 shares                                            8,000,000                        
  noncontrolling interest - wmre preference shares                                            250,000,000 250,000,000  250,000,000 250,000,000 250,000,000  250,000,000 250,000,000 250,000,000               
  white mountains’ common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 7,975,452 and 8,194,925 shares                                             8,000,000                       
  reinsurance recoverable on unpaid losses—berkshire hathaway inc.                                              1,312,200,000    1,573,300,000                  
  white mountains’ common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 8,194,925 and 8,860,150 shares                                              8,200,000                      
  noncontrolling interest—wmre preference shares                                              250,000,000    250,000,000                  
  white mountains’ common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 8,343,050 and 8,860,150 shares                                               8,300,000                     
  assets held for sale - onebeacon personal lines transaction                                                655,600,000                    
  liabilities held for sale - onebeacon personal lines transaction                                                502,300,000                    
  white mountains’ common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 8,532,442 and 8,860,150 shares                                                8,500,000                    
  white mountains’ common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 8,775,632 and 8,860,150 shares                                                 8,800,000                   
  securities lending collateral                                                    92,300,000  341,200,000 474,900,000 481,100,000 824,600,000 554,000,000 563,800,000 649,800,000 583,800,000 453,100,000 496,200,000 674,900,000 786,900,000 564,600,000  
  securities lending payable                                                  1,700,000 1,700,000 96,400,000  349,600,000 476,300,000 481,100,000 824,600,000 554,000,000 563,800,000 649,800,000 583,800,000 453,100,000 496,200,000 674,900,000 786,900,000 564,600,000  
  white mountains’ common shares at 1 par value per share—authorized 50,000,000 shares; issued and outstanding 8,860,150 and 8,808,843 shares                                                  8,900,000                  
  reinsurance recoverable on unpaid losses - berkshire hathaway inc.                                                   1,603,500,000 1,623,900,000 1,655,500,000 1,763,600,000 1,705,400,000 1,740,000,000 1,792,600,000 1,828,900,000 1,867,300,000 1,881,200,000 1,902,300,000  1,968,000,000 2,022,100,000 2,058,800,000 2,077,800,000 2,260,300,000 
  white mountains’ common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 8,857,586 and 8,808,843 shares                                                   8,900,000                 
  incentive compensation payable                                                    107,600,000 71,700,000 160,300,000 142,900,000 118,900,000            
  white mountains’ shareholders’ equity                                                                    
  white mountains common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 8,857,586 and 8,808,843 shares                                                    8,900,000                
  equity in unrealized losses from investments in unconsolidated affiliates                                                                    
  total white mountains shareholders’ equity                                                    3,204,100,000 2,866,200,000               
  securities lending investment assets - onebeacon                                                     46,900,000               
  securities lending collateral - onebeacon                                                                    
  securities lending collateral - wmre america                                                     105,800,000               
  securities lending payable - onebeacon                                                     48,600,000               
  securities lending payable - wmre america                                                     112,800,000               
  white mountains common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 8,854,086 and 8,808,843 shares                                                     8,900,000               
  other investments                                                      583,900,000 666,500,000 642,500,000 549,300,000 558,500,000 532,200,000 524,800,000 498,000,000 469,600,000 506,800,000 588,100,000 507,100,000 533,300,000 239,200,000 
  trust account investments, at amortized cost                                                        309,200,000 308,700,000 312,000,000 335,400,000 338,900,000        
  preferred stock subject to mandatory redemption:                                                                    
  held by berkshire hathaway inc.                                                        288,900,000 268,500,000 259,200,000 250,500,000 242,300,000 234,500,000 227,300,000 220,400,000 214,000,000 207,900,000 202,200,000 174,500,000 
  minority interest - onebeacon ltd.                                                      337,100,000              
  minority interest - wmre group preference shares                                                      250,000,000 250,000,000 250,000,000 250,000,000           
  minority interest - consolidated limited partnerships                                                      91,400,000 98,700,000 97,100,000 102,500,000 111,600,000 113,000,000         
  total minority interest                                                      678,500,000 748,700,000 754,500,000 888,800,000 887,600,000 628,800,000 603,200,000        
  common shareholders’ equity                                                                    
  common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 10,441,964 and 10,553,572 shares                                                      10,400,000              
  net unrealized gains on investments                                                         184,300,000 144,000,000 214,700,000 194,000,000 165,700,000 53,100,000 167,600,000 233,900,000 288,800,000 411,200,000  
  total common shareholders’ equity                                                      4,061,900,000 4,597,300,000 4,679,200,000 4,732,600,000 4,575,300,000 4,542,900,000 4,455,300,000 4,118,700,000 3,864,300,000 3,872,200,000 3,833,200,000 3,882,800,000 4,091,800,000 2,979,200,000 
  total liabilities, minority interest and common shareholders’ equity                                                      17,764,400,000 18,703,800,000 19,364,800,000 19,718,700,000 19,184,300,000 19,278,200,000 19,443,700,000        
  minority interest - onebeacon, ltd.                                                       400,000,000 407,400,000 536,300,000           
  common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 10,552,376 and 10,553,572 shares                                                       10,600,000             
  common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 10,570,234 and 10,553,572 shares                                                        10,600,000            
  long-term incentive compensation payable                                                         202,500,000 181,500,000 139,300,000 285,200,000        
  reserves for structured contracts                                                         78,800,000 87,300,000 142,600,000 147,100,000 153,500,000 214,200,000 222,800,000 224,600,000 268,300,000 278,200,000  
  held by others                                                           20,000,000 20,000,000 20,000,000 20,000,000 20,000,000 20,000,000 20,000,000 20,000,000 20,000,000 
  common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 10,842,613 and 10,782,753 shares                                                         10,800,000           
  minority interest - onebeacon insurance group, ltd.                                                          526,000,000 515,800,000         
  minority interest - white mountains re group, ltd. preference shares                                                          250,000,000          
  common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 10,842,538 and 10,782,753 shares                                                          10,800,000          
  investments in unconsolidated insurance affiliates                                                           356,300,000 335,500,000 529,100,000 412,000,000 437,500,000 479,700,000 486,800,000 531,200,000 515,900,000 
  common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 10,833,788 and 10,782,753 shares                                                           10,800,000         
  minority interest- onebeacon insurance group, ltd.                                                            490,700,000        
  minority interest- consolidated limited partnerships                                                            112,500,000        
  common shares at 1 par value per share — authorized 50,000,000 shares; issued and outstanding 10,782,753 and 10,779,223 shares                                                            10,800,000        
  unearned compensation - restricted common share awards                                                                    
  investment income accrued                                                             81,800,000 89,400,000 84,300,000 93,500,000 91,000,000 96,600,000 73,000,000 
  common shares at 1 par value per share—authorized 50,000,000 shares;issued and outstanding 10,780,053 and 10,779,223 shares                                                             10,800,000       
  minimum pension liability and other                                                                    
  total liabilities and common shareholders’ equity                                                             18,712,100,000 18,728,000,000 19,081,400,000 19,418,100,000 19,795,800,000 19,184,700,000  
  reinsurance recoverable on unpaid losses — berkshire hathaway inc.                                                              1,935,600,000      
  common shares at 1 par value per share — authorized 50,000,000 share issued and outstanding 10,780,053 and 10,779,223 shares                                                              10,800,000      
  accumulated other comprehensive income, after-tax                                                                    
  common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 10,780,053 and 10,779,223 shares                                                               10,800,000     
  common shares at 1 par value per share ­ authorized 50,000,000 shares; issued and outstanding 10,779,223 and 10,772,789 shares                                                                10,800,000    
  common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 10,773,723 and 10,772,789 shares                                                                 10,800,000   
  minimum pension liability                                                                    
  common shares at 1 par value per share - authorized 50,000,000 shares; issued and outstanding 10,774,273 and 10,772,789 shares                                                                  10,800,000  
  convertible preference shares                                                                    
  minority interest - mandatorily redeemable preferred stock of subsidiaries                                                                    
  common shares at 1 par per share– authorized 50,000,000 shares; issued and outstanding 9,007,195 and 8,351,387 shares                                                                   9,000,000 
  unrealized gains on investments                                                                   286,000,000 
  unrealized foreign currency translation losses                                                                    
  total liabilities, convertible preference shares, minority interest and common shareholders’ equity                                                                   14,971,000,000 

We provide you with 20 years of balance sheets for White Mountains Insurance Group stock, allowing you to gain comprehensive visibility into the fundamentals of the company. Our detailed breakdowns include key financial metrics such as asset and liabilities, payables and receivables, long debts and short debts, cash and inventories, expenses and profits. This in-depth information is essential for making informed investment decisions and understanding the financial health and performance of White Mountains Insurance Group. Explore the full financial landscape of White Mountains Insurance Group stock with our expertly curated balance sheets.

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