7Baggers

Aon plc
(NYSE:AON) 

AON stock logo

Aon plc, a professional services firm, provides advice and solutions to clients focused on risk, retirement, and health worldwide. It offers commercial risk solutions, including retail brokerage, cyber, and global risk consulting solutions, as well as acts as a captive insurance solutions provider; ...

Founded: 1982
Full Time Employees: 50,000
Sector: Financial Services
Industry: Insurance Brokers

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At a glance:
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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 2023-09-30 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 2019-12-31 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 2014-09-30 2014-06-30 2014-03-31 2013-03-31 2012-06-30 2012-03-31 2011-09-30 2011-06-30 2011-03-31 2010-09-30 2010-06-30 2010-03-31 2009-09-30 2009-06-30 2009-03-31 2008-09-30 2008-06-30 
                                                                
      revenue
                                                                
      total revenue
    5,034,000,000 4,300,000,000 3,997,000,000 4,155,000,000 4,729,000,000 4,147,000,000 3,721,000,000 3,760,000,000 4,070,000,000 2,953,000,000 3,177,000,000 3,871,000,000 3,130,000,000 2,696,000,000 2,983,000,000 3,670,000,000 3,080,000,000 2,702,000,000 2,886,000,000 3,525,000,000 2,965,000,000 2,385,000,000 2,497,000,000 3,219,000,000 2,885,000,000 2,379,000,000 2,606,000,000 3,143,000,000 2,770,000,000 2,349,000,000 2,561,000,000 3,090,000,000 2,340,000,000 2,368,000,000 2,381,000,000 3,323,000,000 2,746,000,000 2,766,000,000 2,792,000,000 3,288,000,000 2,742,000,000 2,805,000,000 2,847,000,000 2,880,000,000 2,919,000,000 2,947,000,000 2,915,000,000 2,821,000,000 2,841,000,000 2,723,000,000 2,811,000,000 2,759,000,000 1,801,000,000 1,898,000,000 1,904,000,000 1,808,000,000 1,885,000,000 1,854,000,000 1,847,000,000 1,980,000,000 
      yoy
    6.45% 3.69% 7.42% 10.51% 16.19% 40.43% 17.12% -2.87% 30.03% 9.53% 6.50% 5.48% 1.62% -0.22% 3.36% 4.11% 3.88% 13.29% 15.58% 9.51% 2.77% 0.25% -4.18% 2.42% 4.15% 1.28% 1.76% 1.72% 18.38% -0.80% 7.56% -7.01% -14.79% -14.39% -14.72% 1.06% 0.15% -1.39% -1.93% 14.17% -6.06% -4.82% -2.33% 2.09% 2.75% 8.23% 3.70% 2.25% 57.75% 43.47% 47.64% 52.60% -4.46% 2.37% 3.09% -8.69%     
      qoq
    17.07% 7.58% -3.80% -12.14% 14.03% 11.45% -1.04% -7.62% 37.83% -7.05% -17.93% 23.67% 16.10% -9.62% -18.72% 19.16% 13.99% -6.38% -18.13% 18.89% 24.32% -4.49% -22.43% 11.58% 21.27% -8.71% -17.09% 13.47% 17.92% -8.28% -17.12% 32.05% -1.18% -0.55% -28.35% 21.01% -0.72% -0.93% -15.09% 19.91% -2.25% -1.48% -1.15% -1.34% -0.95% 1.10% 3.33% -0.70% 4.33% -3.13% 1.88% 53.19% -5.11% -0.32% 5.31% -4.08% 1.67% 0.38% -6.72%  
      expenses
                                                                
      compensation and benefits
    2,393,000,000 2,117,000,000 2,259,000,000 2,360,000,000 2,249,000,000 2,120,000,000 2,150,000,000 2,130,000,000 1,883,000,000 1,685,000,000 1,754,000,000 1,792,000,000 1,539,000,000 1,532,000,000 1,639,000,000 1,767,000,000 1,556,000,000 1,835,000,000 1,628,000,000 1,719,000,000 1,635,000,000 1,387,000,000 1,361,000,000 1,522,000,000 1,601,000,000 1,368,000,000 1,501,000,000 1,584,000,000 1,601,000,000 1,392,000,000 1,494,000,000 1,616,000,000 1,419,000,000 1,457,000,000 1,461,000,000 1,966,000,000 1,611,000,000 1,688,000,000 1,649,000,000 1,857,000,000 1,644,000,000 1,653,000,000 1,683,000,000 1,707,000,000 1,708,000,000 1,751,000,000 1,725,000,000 1,639,000,000 1,661,000,000 1,634,000,000 1,612,000,000 1,597,000,000 1,050,000,000 1,169,000,000 1,163,000,000 1,119,000,000 1,134,000,000 1,014,000,000 1,132,000,000 1,155,000,000 
      information technology
    144,000,000 156,000,000 140,000,000 136,000,000 136,000,000 142,000,000 141,000,000 132,000,000 124,000,000 135,000,000 129,000,000 139,000,000 138,000,000 133,000,000 115,000,000 123,000,000 118,000,000 130,000,000 115,000,000 114,000,000 119,000,000 107,000,000 107,000,000 111,000,000 131,000,000 120,000,000 126,000,000 117,000,000 121,000,000 125,000,000 123,000,000 115,000,000 109,000,000 98,000,000 88,000,000                          
      premises
    81,000,000 85,000,000 85,000,000 85,000,000 82,000,000 84,000,000 88,000,000 82,000,000 71,000,000 74,000,000 68,000,000 75,000,000 73,000,000 71,000,000 73,000,000 72,000,000 76,000,000 98,000,000 76,000,000 77,000,000 74,000,000 70,000,000 74,000,000 73,000,000 91,000,000 76,000,000 85,000,000 87,000,000 87,000,000 94,000,000 96,000,000 93,000,000 89,000,000 86,000,000 84,000,000                          
      depreciation of fixed assets
    46,000,000 48,000,000 47,000,000 47,000,000 46,000,000 47,000,000 47,000,000 45,000,000 44,000,000 42,000,000 39,000,000 38,000,000 36,000,000 37,000,000 40,000,000 38,000,000 41,000,000 56,000,000 41,000,000 41,000,000 43,000,000 42,000,000 41,000,000 41,000,000 48,000,000 44,000,000 40,000,000 40,000,000 50,000,000 40,000,000 47,000,000 39,000,000 40,000,000 54,000,000 54,000,000                          
      amortization and impairment of intangible assets
    152,000,000 185,000,000 193,000,000 201,000,000 199,000,000 185,000,000 174,000,000 128,000,000 16,000,000 20,000,000 25,000,000 25,000,000 26,000,000 34,000,000 25,000,000 28,000,000 35,000,000 36,000,000       97,000,000 101,000,000 97,000,000 97,000,000 101,000,000 100,000,000 282,000,000 110,000,000 101,000,000 460,000,000                           
      other general expense
    411,000,000 372,000,000 425,000,000 373,000,000 446,000,000 409,000,000 429,000,000 455,000,000 348,000,000 300,000,000 320,000,000 329,000,000 306,000,000 299,000,000 391,000,000 275,000,000 280,000,000 1,348,000,000 318,000,000 289,000,000 340,000,000 288,000,000 262,000,000 342,000,000 393,000,000 310,000,000                                   
      accelerating aon united program expenses
    92,000,000 129,000,000 32,000,000 94,000,000 110,000,000 69,000,000 69,000,000 132,000,000 119,000,000 6,000,000                                                   
      total operating expenses
    3,319,000,000 3,092,000,000 3,181,000,000 3,296,000,000 3,268,000,000 3,056,000,000 3,098,000,000 3,104,000,000 2,605,000,000 2,262,000,000 2,335,000,000 2,398,000,000 2,118,000,000 2,106,000,000 2,283,000,000 2,303,000,000 2,106,000,000 3,503,000,000 2,214,000,000 2,280,000,000 2,252,000,000 1,944,000,000 1,903,000,000 2,186,000,000 2,361,000,000 2,019,000,000 2,193,000,000 2,271,000,000 2,271,000,000 2,087,000,000 2,577,000,000 2,291,000,000 2,075,000,000 2,486,000,000 2,038,000,000 2,694,000,000 2,324,000,000 2,361,000,000 2,342,000,000 2,571,000,000 2,329,000,000 2,528,000,000 2,406,000,000 2,463,000,000 2,474,000,000 2,478,000,000 2,505,000,000 2,427,000,000 2,439,000,000 2,382,000,000 2,377,000,000 2,363,000,000 1,538,000,000 1,630,000,000 1,631,000,000 1,599,000,000 1,658,000,000 1,471,000,000 1,606,000,000 1,725,000,000 
      operating income
    1,715,000,000 1,208,000,000 816,000,000 859,000,000 1,461,000,000 1,091,000,000 623,000,000 656,000,000 1,465,000,000 691,000,000 842,000,000 1,473,000,000 1,012,000,000 590,000,000 700,000,000 1,367,000,000 974,000,000 -801,000,000 672,000,000 1,245,000,000 713,000,000 441,000,000 594,000,000 1,033,000,000 524,000,000 360,000,000 413,000,000 872,000,000 499,000,000 262,000,000 -16,000,000 799,000,000 265,000,000 -118,000,000 343,000,000 629,000,000 422,000,000 405,000,000 450,000,000 717,000,000 413,000,000 277,000,000 441,000,000 417,000,000 445,000,000 469,000,000 410,000,000 394,000,000 402,000,000 341,000,000 434,000,000 396,000,000 263,000,000 268,000,000 273,000,000      
      yoy
    17.39% 10.72% 30.98% 30.95% -0.27% 57.89% -26.01% -55.47% 44.76% 17.12% 20.29% 7.75% 3.90% -173.66% 4.17% 9.80% 36.61% -281.63% 13.13% 20.52% 36.07% 22.50% 43.83% 18.46% 5.01% 37.40% -2681.25% 9.14% 88.30% -322.03% -104.66% 27.03% -37.20% -129.14% -23.78% -12.27% 2.18% 46.21% 2.04% 71.94% -7.19% -40.94% 7.56% 5.84% 10.70% 37.54% -5.53% -0.51% 52.85% 27.24% 58.97%          
      qoq
    41.97% 48.04% -5.01% -41.20% 33.91% 75.12% -5.03% -55.22% 112.01% -17.93% -42.84% 45.55% 71.53% -15.71% -48.79% 40.35% -221.60% -219.20% -46.02% 74.61% 61.68% -25.76% -42.50% 97.14% 45.56% -12.83% -52.64% 74.75% 90.46% -1737.50% -102.00% 201.51% -324.58% -134.40% -45.47% 49.05% 4.20% -10.00% -37.24% 73.61% 49.10% -37.19% 5.76% -6.29% -5.12% 14.39% 4.06% -1.99% 17.89% -21.43% 9.60% 50.57% -1.87% -1.83%       
      operating margin %
    34.07% 28.09% 20.42% 20.67% 30.89% 26.31% 16.74% 17.45% 36.00% 23.40% 26.50% 38.05% 32.33% 21.88% 23.47% 37.25% 31.62% -29.64% 23.28% 35.32% 24.05% 18.49% 23.79% 32.09% 18.16% 15.13% 15.85% 27.74% 18.01% 11.15% -0.62% 25.86% 11.32% -4.98% 14.41% 18.93% 15.37% 14.64% 16.12% 21.81% 15.06% 9.88% 15.49% 14.48% 15.24% 15.91% 14.07% 13.97% 14.15% 12.52% 15.44% 14.35% 14.60% 14.12% 14.34% 0% 0% 0% 0% 0% 
      interest income
    12,000,000 14,000,000   5,000,000 4,000,000 4,000,000 31,000,000 28,000,000 9,000,000 5,000,000 5,000,000 3,000,000 7,000,000 5,000,000 3,000,000 2,000,000 3,000,000 3,000,000 3,000,000 1,000,000 3,000,000  2,000,000 4,000,000 1,000,000 1,000,000 2,000,000   1,000,000 4,000,000 10,000,000 8,000,000 2,000,000 3,000,000 1,000,000 3,000,000 2,000,000 4,000,000 3,000,000 4,000,000 3,000,000 3,000,000 2,000,000 2,000,000 1,000,000 2,000,000 3,000,000 4,000,000 4,000,000 6,000,000 4,000,000 4,000,000 1,000,000      
      interest expense
    -179,000,000 -191,000,000 -206,000,000 -212,000,000 -206,000,000 -206,000,000 -213,000,000 -225,000,000 -144,000,000 -119,000,000 -130,000,000 -111,000,000 -110,000,000 -103,000,000 -102,000,000 -91,000,000 -85,000,000 -80,000,000 -78,000,000 -79,000,000 -82,000,000 -80,000,000 -89,000,000 -83,000,000 -80,000,000 -78,000,000 -77,000,000 -72,000,000 -70,000,000 -69,000,000 -69,000,000 -70,000,000 -70,000,000 -71,000,000 -70,000,000 -70,000,000 -70,000,000 -73,000,000 -69,000,000 -68,000,000 -72,000,000 -68,000,000 -65,000,000 -65,000,000 -65,000,000 -58,000,000 -52,000,000         32,000,000 26,000,000 29,000,000 32,000,000 31,000,000 
      other income
    5,000,000 1,178,000,000 -13,000,000 56,000,000 -10,000,000 2,000,000 35,000,000 236,000,000 75,000,000 -21,000,000 -59,000,000 -25,000,000 -196,000,000 16,000,000 30,000,000 25,000,000 145,000,000 10,000,000 -1,000,000 -2,000,000 -6,000,000 -1,000,000 -10,000,000 29,000,000 -7,000,000 2,000,000 6,000,000  -8,000,000 1,000,000 -3,000,000 -15,000,000 -5,000,000 -5,000,000 -10,000,000 9,000,000 9,000,000  18,000,000 49,000,000 8,000,000 1,000,000 42,000,000 35,000,000 -2,000,000 1,000,000 9,000,000 12,000,000  7,000,000  17,000,000  5,000,000 7,000,000      
      income before income taxes
    1,553,000,000 2,209,000,000 597,000,000 703,000,000 1,250,000,000 891,000,000 449,000,000 698,000,000 1,424,000,000 560,000,000 658,000,000 1,342,000,000 709,000,000 510,000,000 633,000,000 1,304,000,000 1,036,000,000 -868,000,000 596,000,000 1,167,000,000                571,000,000 362,000,000 335,000,000 401,000,000 702,000,000 352,000,000 214,000,000 421,000,000 390,000,000 380,000,000 414,000,000 368,000,000              
      income tax expense
    314,000,000 505,000,000 127,000,000 109,000,000 268,000,000 157,000,000 94,000,000 160,000,000 331,000,000 93,000,000 83,000,000 263,000,000 43,000,000 92,000,000 119,000,000 256,000,000 163,000,000 23,000,000 203,000,000 234,000,000 92,000,000 82,000,000 85,000,000 189,000,000 59,000,000 56,000,000 56,000,000  2,250,000 39,000,000   4,000,000 -143,000,000                           
      net income
    1,239,000,000 1,704,000,000 470,000,000 594,000,000 982,000,000 734,000,000 355,000,000 538,000,000 1,093,000,000 467,000,000 575,000,000 1,079,000,000 666,000,000 418,000,000 514,000,000 1,048,000,000 873,000,000 -891,000,000 393,000,000 933,000,000 534,000,000 282,000,000 411,000,000 791,000,000 382,000,000 228,000,000 287,000,000 676,000,000 353,000,000 153,000,000 58,000,000 610,000,000 192,000,000 778,000,000 305,000,000 509,000,000 314,000,000 280,000,000 327,000,000 590,000,000 303,000,000 188,000,000 341,000,000 315,000,000 313,000,000 336,000,000 272,000,000 254,000,000 249,000,000 208,000,000 267,000,000 255,000,000 147,000,000 158,000,000 186,000,000 134,000,000 155,000,000 285,000,000 117,000,000 1,133,000,000 
      yoy
    26.17% 132.15% 32.39% 10.41% -10.16% 57.17% -38.26% -50.14% 64.11% 11.72% 11.87% 2.96% -23.71% -146.91% 30.79% 12.33% 63.48% -415.96% -4.38% 17.95% 39.79% 23.68% 43.21% 17.01% 8.22% 49.02% 394.83% 10.82% 83.85% -80.33% -80.98% 19.84% -38.85% 177.86% -6.73% -13.73% 3.63% 48.94% -4.11% 87.30% -3.19% -44.05% 25.37% 24.02% 25.70% 61.54% 1.87% -0.39% 69.39% 31.65% 43.55% 90.30% -5.16% -44.56% 58.97% -88.17%     
      qoq
    -27.29% 262.55% -20.88% -39.51% 33.79% 106.76% -34.01% -50.78% 134.05% -18.78% -46.71% 62.01% 59.33% -18.68% -50.95% 20.05% -197.98% -326.72% -57.88% 74.72% 89.36% -31.39% -48.04% 107.07% 67.54% -20.56% -57.54% 91.50% 130.72% 163.79% -90.49% 217.71% -75.32% 155.08% -40.08% 62.10% 12.14% -14.37% -44.58% 94.72% 61.17% -44.87% 8.25% 0.64% -6.85% 23.53% 7.09% 2.01% 19.71% -22.10% 4.71% 73.47% -6.96% -15.05% 38.81% -13.55% -45.61% 143.59% -89.67%  
      net income margin %
    24.61% 39.63% 11.76% 14.30% 20.77% 17.70% 9.54% 14.31% 26.86% 15.81% 18.10% 27.87% 21.28% 15.50% 17.23% 28.56% 28.34% -32.98% 13.62% 26.47% 18.01% 11.82% 16.46% 24.57% 13.24% 9.58% 11.01% 21.51% 12.74% 6.51% 2.26% 19.74% 8.21% 32.85% 12.81% 15.32% 11.43% 10.12% 11.71% 17.94% 11.05% 6.70% 11.98% 10.94% 10.72% 11.40% 9.33% 9.00% 8.76% 7.64% 9.50% 9.24% 8.16% 8.32% 9.77% 7.41% 8.22% 15.37% 6.33% 57.22% 
      less: net income attributable to redeemable and nonredeemable noncontrolling interests
    27,000,000 11,000,000 12,000,000 15,000,000 17,000,000                                                        
      net income attributable to aon shareholders
    1,212,000,000 1,693,000,000 458,000,000 579,000,000 965,000,000 716,000,000 343,000,000 524,000,000 1,071,000,000 456,000,000 560,000,000 1,050,000,000 657,000,000 408,000,000 501,000,000 1,023,000,000 863,000,000 -900,000,000 379,000,000 913,000,000 524,000,000 275,000,000 398,000,000 772,000,000 374,000,000 222,000,000 277,000,000 659,000,000 345,000,000 147,000,000 48,000,000 594,000,000 185,000,000 769,000,000 291,000,000 502,000,000 307,000,000 272,000,000 315,000,000 584,000,000 295,000,000 178,000,000 328,000,000 309,000,000 304,000,000 325,000,000 261,000,000 246,000,000             
      basic net income per share attributable to aon shareholders
    5.66 7.85 2.12 2.68 4.46 3.31 1.58 2.47 5.38 2.25 2.74 5.09 3.17 1.93 2.35 4.75 3.86 -3.99 1.67 4.02                1.89 1.15 1.01 1.16 2.1 1.05 0.63 1.15 1.06 1.02 1.07 0.82              
      diluted net income per share attributable to aon shareholders
    5.63 7.81 2.11 2.66 4.43 3.29 1.57 2.46 5.35 2.23 2.71 5.07 3.14 1.92 2.33 4.73 3.83 -3.99 1.66                1.86 1.14 1.01 1.15 2.08 1.04 0.62 1.14 1.04 1.01 1.06 0.82              
      weighted-average ordinary shares outstanding - basic
    214.3 215.9 215.7 216.2 216.4 211.4 217.4 212.5 199.1 202.9 204.7 206.1 211.7 210.9 213.3 215.3 224.7 225.4 227 227.1 231.9 232.6 232.7 233.2 238.6 236.9 240.6 242.2 245.2 244 246 248.5 255.6 262.4 264.8 268.1 267.5 268 271.7 280.8 280.9 284.5 284.2 292.3 298.5 303.5 316.4 332             
      weighted-average ordinary shares outstanding - diluted
    215.4 217.1 216.7 217.3 217.9 212.5 218.4 213.3 200.1 204.6 206.3 207.1 213.2 212.6 214.7 216.4 226.1 225.4 228 228.1 233.1 233.5 233.6 234.5 240.6 239.1 242.8 243.7 247 245.6 247.4 250.2 257.3 262.4 267 270.3 269.6 269.8 273.7 283.8 283.8 286.7 287.1 296.1 301.6 307.2 320 335.6             
      less: net income attributable to redeemable and non-redeemable noncontrolling interests
         12,000,000 12,000,000 14,000,000                                                     
      less: net income attributable to noncontrolling interests
            22,000,000 11,000,000 15,000,000 29,000,000 9,000,000 10,000,000 13,000,000 25,000,000 10,000,000 9,000,000 14,000,000 20,000,000 10,000,000 7,000,000 13,000,000 19,000,000 8,000,000 6,000,000 10,000,000 17,000,000 8,000,000 6,000,000 10,000,000 16,000,000 7,000,000 9,000,000 14,000,000 7,000,000 7,000,000 8,000,000 12,000,000 6,000,000 8,000,000 10,000,000 13,000,000 6,000,000 9,000,000 11,000,000 11,000,000 8,000,000 11,000,000 10,000,000 9,000,000 9,000,000 3,000,000 5,000,000 8,000,000 14,000,000 6,000,000 5,000,000   
      amortization of intangible assets
                      36,000,000 40,000,000 51,250,000 50,000,000 58,000,000 97,000,000           43,000,000                          
      income from continuing operations before income taxes
                        626,000,000 363,000,000 495,000,000 981,000,000 441,000,000 285,000,000 343,000,000 802,000,000 421,000,000 194,000,000 -87,000,000 718,000,000 200,000,000 -186,000,000 265,000,000             351,000,000 346,000,000 292,000,000 352,000,000 356,000,000 208,000,000 244,000,000 247,000,000 178,000,000 210,000,000 343,000,000   
      net income from continuing operations
                        534,000,000 281,000,000 410,000,000 792,000,000 382,000,000 229,000,000 287,000,000 676,000,000 284,000,000 155,000,000 57,000,000 604,000,000 196,000,000 -43,000,000                           
      net income from discontinued operations
                         1,000,000 1,000,000 -1,000,000  -1,000,000   69,000,000 -2,000,000 1,000,000 6,000,000                             
      continuing operations
                        2.28 1.18 1.71 3.31 1.59 0.94 1.15 2.72 1.14 0.61 0.19 2.37 0.74 -0.2 0.95             0.74 0.72 0.59 0.76 0.72 0.52 0.64 0.65 0.41 0.52  0.56 0.58 
      discontinued operations
                                0.28 -0.01 0.01 0.02 -0.02 3.13 0.15                     0.01 0.01 0.18  3.33 
      other general expenses
                              344,000,000 346,000,000 311,000,000 336,000,000 535,000,000 318,000,000 317,000,000 331,000,000 308,000,000 728,000,000 713,000,000 673,000,000 693,000,000 714,000,000 685,000,000 875,000,000 723,000,000 756,000,000 766,000,000 727,000,000 780,000,000 788,000,000 778,000,000 748,000,000 765,000,000 766,000,000 488,000,000 461,000,000 468,000,000 424,000,000 466,000,000 397,000,000 425,000,000 512,000,000 
      income taxes
                               126,000,000    114,000,000    62,000,000 48,000,000 55,000,000 74,000,000 112,000,000 49,000,000 26,000,000 80,000,000 75,000,000 67,000,000 78,000,000 96,000,000 96,000,000 97,000,000 84,000,000 87,000,000 103,000,000 61,000,000 60,000,000 61,000,000 47,000,000 57,000,000 108,000,000   
      cash dividends per share paid on ordinary shares
                                0.29 0.4 0.4 0.36 0.36 0.36 0.33 0.33 0.33 0.33 0.3 0.3 0.3 0.3 0.25 0.25 0.25 0.18 0.16 0.16             
      income tax benefit
                                  -144,000,000                              
      income from discontinued operations, net of tax
                                    -4,000,000 821,000,000 40,000,000                         965,000,000 
      income from continuing operations
                                      265,000,000             255,000,000 249,000,000 208,000,000 265,000,000 253,000,000 147,000,000 184,000,000 186,000,000 131,000,000 153,000,000 235,000,000 153,000,000 168,000,000 
      commissions, fees and other
                                       3,317,000,000 2,740,000,000 2,761,000,000 2,787,000,000 3,283,000,000 2,736,000,000 2,800,000,000 2,842,000,000 2,873,000,000 2,913,000,000 2,941,000,000 2,908,000,000 2,813,000,000 2,829,000,000 2,708,000,000 2,799,000,000 2,748,000,000 1,786,000,000 1,883,000,000 1,891,000,000 1,780,000,000 1,864,000,000 1,822,000,000 1,756,000,000 1,912,000,000 
      fiduciary investment income
                                       6,000,000 6,000,000 5,000,000 5,000,000 5,000,000 6,000,000 5,000,000 5,000,000 7,000,000 6,000,000 6,000,000 7,000,000 8,000,000 12,000,000 15,000,000 12,000,000 11,000,000 15,000,000 15,000,000 13,000,000      
      income from discontinued operations before income taxes
                                                      1,000,000 4,000,000 1,000,000  2,000,000  2,000,000 91,000,000   
      income from discontinued operations
                                                      2,000,000 2,000,000    3,000,000 2,000,000 50,000,000  1,428,000,000 
      net income attributable to aon stockholders
                                                    238,000,000 198,000,000 258,000,000 246,000,000 144,000,000 153,000,000 178,000,000 120,000,000 149,000,000 280,000,000   
      basic net income per share attributable to aon stockholders
                                                                
      diluted net income per share attributable to aon stockholders
                                                                
      cash dividends per share paid on common stock
                                                    0.15 0.15 0.15 0.15 0.15 0.15 0.15    0.15 0.15 
      weighted-average common shares outstanding - basic
                                                    332.4 332.6 337.7 339.4  278.4  283.8  284.3   
      weighted-average common shares outstanding - diluted
                                                    336.6 336.9 342.7 345.4 282.2 282.6 283.4 292.1 289.1 288.8 290.3 305.3 
      weighted average common shares outstanding - basic
                                                        278.7  275.9  278.3    
      investment income
                                                           28,000,000 21,000,000 32,000,000 91,000,000 68,000,000 
      depreciation and amortization
                                                           56,000,000 58,000,000 60,000,000 49,000,000 58,000,000 
      other expense
                                                             11,000,000   
      dividends paid per share
                                                           0.15 0.15 0.15   
      income from continuing operations before provision for income tax
                                                              212,000,000 226,000,000 
      provision for income tax
                                                              59,000,000 58,000,000 
      basic net income per share
                                                                
      diluted net income per share
                                                                
    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 2023-09-30 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 2019-12-31 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 2014-09-30 2014-06-30 2014-03-31 2013-03-31 2012-06-30 2012-03-31 2011-09-30 2011-06-30 2011-03-31 2010-09-30 2010-06-30 2010-03-31 2009-09-30 2009-06-30 2009-03-31 2008-09-30 2008-06-30 2008-03-31 2007-09-30 2007-06-30 2007-03-31 2006-09-30 2006-06-30 2006-03-31 
                                                                         
        assets
                                                                         
        current assets
                                                                         
        cash and cash equivalents
      1,178,000,000 1,195,000,000 1,095,000,000 1,008,000,000 964,000,000 1,085,000,000 1,103,000,000 974,000,000 995,000,000 808,000,000 952,000,000 1,119,000,000 690,000,000 692,000,000 740,000,000 595,000,000 544,000,000 609,000,000 1,091,000,000 822,000,000 884,000,000 821,000,000 757,000,000 690,000,000 790,000,000 602,000,000 581,000,000 600,000,000 656,000,000 484,000,000 487,000,000 597,000,000 749,000,000 684,000,000 433,000,000 431,000,000 483,000,000 438,000,000 465,000,000 384,000,000 398,000,000 367,000,000 378,000,000 382,000,000 418,000,000 338,000,000 408,000,000 286,000,000 323,000,000 295,000,000 300,000,000 682,000,000 335,000,000 260,000,000 422,000,000 580,000,000 537,000,000 501,000,000          
        short-term investments
      238,000,000 1,603,000,000 207,000,000 379,000,000 366,000,000 219,000,000 196,000,000 182,000,000 5,413,000,000 175,000,000 200,000,000 172,000,000 452,000,000 251,000,000 243,000,000 455,000,000 292,000,000 310,000,000 289,000,000 171,000,000 308,000,000 448,000,000 654,000,000 170,000,000 138,000,000 177,000,000 235,000,000 134,000,000 172,000,000 167,000,000 173,000,000 118,000,000 1,640,000,000 2,746,000,000 200,000,000 290,000,000 463,000,000 251,000,000 587,000,000 356,000,000 385,000,000 484,000,000 343,000,000 217,000,000 308,000,000 340,000,000 352,000,000 516,000,000 510,000,000 607,000,000 515,000,000 589,000,000 2,114,000,000 474,000,000 312,000,000 602,000,000 580,000,000 879,000,000 1,946,000,000 2,566,000,000 771,000,000 4,096,000,000 4,199,000,000 4,314,000,000 3,647,000,000 4,136,000,000 4,702,000,000 
        receivables
      5,089,000,000 4,209,000,000 4,276,000,000 4,905,000,000 4,620,000,000 3,803,000,000 4,004,000,000 4,459,000,000 4,035,000,000 3,300,000,000 3,764,000,000 3,713,000,000 3,035,000,000 2,971,000,000 3,648,000,000 3,625,000,000 3,094,000,000 3,117,000,000 3,545,000,000 3,526,000,000 3,070,000,000 2,906,000,000 3,314,000,000 3,554,000,000 3,112,000,000 2,866,000,000 3,227,000,000 3,242,000,000 2,760,000,000 2,656,000,000 2,992,000,000 3,053,000,000 2,068,000,000 2,191,000,000 2,103,000,000 2,589,000,000 2,391,000,000 2,516,000,000 2,591,000,000 2,734,000,000 2,453,000,000 2,684,000,000 2,672,000,000 2,630,000,000 2,803,000,000 2,880,000,000 2,884,000,000 3,075,000,000 3,164,000,000 2,745,000,000 2,785,000,000 2,650,000,000 2,086,000,000 1,994,000,000 1,983,000,000 1,844,000,000 1,937,000,000 1,795,000,000 1,877,000,000 2,012,000,000 1,938,000,000       
        fiduciary assets
      18,905,000,000 17,889,000,000 18,781,000,000 20,677,000,000 17,766,000,000 17,566,000,000 17,596,000,000 18,865,000,000 17,161,000,000 15,965,000,000 18,193,000,000 16,629,000,000 15,900,000,000 14,699,000,000 16,864,000,000 15,277,000,000 14,386,000,000 14,017,000,000 15,804,000,000 13,894,000,000 13,798,000,000 13,549,000,000 13,794,000,000 12,401,000,000 11,834,000,000 11,041,000,000 12,071,000,000 11,412,000,000 10,166,000,000 9,314,000,000 10,476,000,000 10,738,000,000 9,292,000,000 9,582,000,000 9,162,000,000 9,485,000,000 8,710,000,000 10,201,000,000 9,776,000,000 9,932,000,000 9,956,000,000 11,389,000,000 10,894,000,000 10,815,000,000 12,786,000,000 12,038,000,000 12,224,000,000 12,736,000,000 11,795,000,000 10,315,000,000 11,760,000,000 10,609,000,000 9,545,000,000 12,226,000,000 11,089,000,000 9,551,000,000 12,323,000,000 11,239,000,000 9,109,000,000 11,358,000,000        
        other current assets
      753,000,000 878,000,000 2,210,000,000 854,000,000 698,000,000 759,000,000 754,000,000 1,063,000,000 1,020,000,000 877,000,000 840,000,000 511,000,000 646,000,000 563,000,000 672,000,000 593,000,000 716,000,000 687,000,000 547,000,000 492,000,000 624,000,000 525,000,000 471,000,000 530,000,000 602,000,000 631,000,000 631,000,000 531,000,000 618,000,000 727,000,000 732,000,000 609,000,000 518,000,000 399,000,000 309,000,000 351,000,000 424,000,000 395,000,000 622,000,000 566,000,000 728,000,000 731,000,000 712,000,000 711,000,000 1,396,000,000 577,000,000 389,000,000 443,000,000 415,000,000 538,000,000 571,000,000 681,000,000 532,000,000 543,000,000 462,000,000 349,000,000 315,000,000 307,000,000 245,000,000 229,000,000 223,000,000       
        total current assets
      26,163,000,000 25,774,000,000 26,569,000,000 27,823,000,000 24,414,000,000 23,432,000,000 23,653,000,000 25,543,000,000 28,624,000,000 21,125,000,000 23,949,000,000 22,144,000,000 20,723,000,000 19,176,000,000 22,167,000,000 20,545,000,000 19,032,000,000 18,740,000,000 21,276,000,000 18,905,000,000 18,684,000,000 18,249,000,000 18,990,000,000 17,345,000,000 16,476,000,000 15,317,000,000 16,745,000,000 15,919,000,000 14,372,000,000 13,348,000,000 14,860,000,000 15,115,000,000 14,267,000,000 15,602,000,000 15,393,000,000 13,146,000,000 12,471,000,000 13,801,000,000 14,041,000,000 13,972,000,000 13,920,000,000 15,655,000,000 14,999,000,000 14,755,000,000 17,711,000,000 16,173,000,000 16,257,000,000 17,056,000,000 16,207,000,000 14,500,000,000 15,931,000,000 15,211,000,000 14,612,000,000 15,497,000,000 14,268,000,000 12,926,000,000 15,881,000,000 14,909,000,000 13,686,000,000 16,631,000,000 19,019,000,000       
        goodwill
      15,925,000,000 15,797,000,000 15,704,000,000 16,024,000,000 15,697,000,000 15,234,000,000 15,612,000,000 15,281,000,000 8,302,000,000 8,245,000,000 8,360,000,000 8,319,000,000 8,292,000,000 7,979,000,000 8,295,000,000 8,496,000,000 8,434,000,000 8,547,000,000 8,659,000,000 8,587,000,000 8,666,000,000 8,462,000,000 8,356,000,000 8,293,000,000 8,165,000,000 8,071,000,000 8,198,000,000 8,219,000,000 8,171,000,000 8,282,000,000 8,291,000,000 8,550,000,000 7,888,000,000 7,745,000,000 7,544,000,000 8,747,000,000 8,452,000,000 8,473,000,000 8,411,000,000 8,448,000,000 8,571,000,000 8,661,000,000 8,548,000,000 9,026,000,000 9,099,000,000 9,030,000,000 8,786,000,000 8,713,000,000 8,896,000,000 8,835,000,000 8,975,000,000 8,895,000,000 5,976,000,000 5,710,000,000 5,887,000,000 5,957,000,000 5,883,000,000 5,546,000,000 4,882,000,000 5,137,000,000 5,175,000,000 4,883,000,000 4,739,000,000 4,698,000,000 4,410,000,000 4,390,000,000 4,423,000,000 
        intangible assets
      5,826,000,000 5,727,000,000 5,827,000,000 6,733,000,000 6,865,000,000 6,743,000,000 6,789,000,000 6,794,000,000 217,000,000 252,000,000 268,000,000 425,000,000 447,000,000 456,000,000 491,000,000 530,000,000 492,000,000 529,000,000 564,000,000 594,000,000 640,000,000 665,000,000 699,000,000 746,000,000 783,000,000 874,000,000 973,000,000 1,077,000,000 1,149,000,000 1,260,000,000 1,363,000,000 1,662,000,000 1,341,000,000 1,402,000,000 1,886,000,000 2,223,000,000 2,038,000,000 2,107,000,000 2,108,000,000 2,180,000,000 2,257,000,000 2,350,000,000 2,410,000,000 2,612,000,000 2,468,000,000 2,500,000,000 2,844,000,000 3,106,000,000 3,203,000,000 3,361,000,000 3,484,000,000 3,547,000,000 754,000,000 753,000,000 770,000,000             
        fixed assets
      714,000,000 702,000,000 684,000,000 664,000,000 650,000,000 637,000,000 650,000,000 636,000,000 590,000,000 652,000,000 639,000,000 605,000,000 558,000,000 510,000,000 505,000,000 515,000,000 529,000,000 541,000,000 585,000,000 584,000,000 599,000,000 609,000,000 615,000,000 666,000,000 621,000,000 606,000,000 599,000,000 606,000,000 588,000,000 594,000,000 575,000,000 578,000,000 545,000,000 556,000,000 536,000,000 765,000,000 738,000,000 751,000,000 766,000,000 765,000,000 785,000,000 782,000,000 754,000,000 760,000,000 787,000,000 785,000,000 816,000,000 797,000,000 808,000,000 773,000,000 798,000,000 791,000,000 468,000,000 450,000,000 452,000,000 453,000,000 447,000,000 430,000,000 449,000,000 483,000,000 507,000,000       
        operating lease right-of-use assets
      674,000,000 677,000,000 681,000,000 735,000,000 716,000,000 711,000,000 737,000,000 723,000,000 628,000,000 646,000,000 678,000,000 684,000,000 699,000,000 668,000,000 704,000,000 754,000,000 786,000,000 823,000,000 863,000,000 867,000,000 911,000,000 914,000,000 941,000,000 897,000,000 929,000,000 913,000,000 959,000,000 993,000,000                                        
        deferred tax assets
      737,000,000 748,000,000 855,000,000 861,000,000 768,000,000 654,000,000 1,209,000,000 1,218,000,000 1,254,000,000 1,022,000,000 963,000,000 897,000,000 824,000,000 819,000,000 771,000,000 770,000,000 766,000,000 761,000,000 738,000,000 721,000,000 724,000,000 655,000,000 654,000,000 638,000,000 645,000,000 611,000,000 599,000,000 588,000,000 561,000,000 476,000,000 452,000,000 296,000,000 565,000,000 575,000,000 351,000,000 322,000,000                                
        prepaid pension
      598,000,000 603,000,000 588,000,000 598,000,000 595,000,000 556,000,000 650,000,000 629,000,000 627,000,000 673,000,000 691,000,000 672,000,000 652,000,000 1,140,000,000 1,284,000,000 1,361,000,000 1,366,000,000 1,350,000,000 1,349,000,000 1,321,000,000 1,280,000,000 1,249,000,000 1,192,000,000 1,164,000,000 1,216,000,000 1,213,000,000 1,213,000,000 1,224,000,000 1,133,000,000 1,208,000,000 1,272,000,000 1,207,000,000 1,020,000,000 941,000,000 893,000,000 858,000,000 711,000,000 720,000,000 737,000,000 1,033,000,000                            
        other non-current assets
      792,000,000 756,000,000 729,000,000 572,000,000 599,000,000 998,000,000 585,000,000 629,000,000 525,000,000 497,000,000 501,000,000 507,000,000 509,000,000 475,000,000 503,000,000 520,000,000 512,000,000 525,000,000 546,000,000 596,000,000 610,000,000 556,000,000 548,000,000 533,000,000 570,000,000 562,000,000 521,000,000 509,000,000 448,000,000 434,000,000 404,000,000 439,000,000 298,000,000 368,000,000 379,000,000 554,000,000 564,000,000 576,000,000 579,000,000 625,000,000 1,673,000,000 1,755,000,000 1,678,000,000 1,531,000,000 1,573,000,000 1,446,000,000 1,174,000,000 935,000,000 946,000,000 1,022,000,000 1,059,000,000 1,040,000,000 1,247,000,000 1,245,000,000 1,274,000,000 1,245,000,000 1,155,000,000 1,172,000,000 1,109,000,000 1,165,000,000 1,151,000,000       
        total assets
      51,429,000,000 50,784,000,000 51,637,000,000 54,010,000,000 50,304,000,000 48,965,000,000 49,885,000,000 51,453,000,000 40,767,000,000 33,112,000,000 36,049,000,000 34,253,000,000 32,704,000,000 31,223,000,000 34,720,000,000 33,491,000,000 31,917,000,000 31,816,000,000 34,580,000,000 32,175,000,000 32,114,000,000 31,359,000,000 31,995,000,000 30,282,000,000 29,405,000,000 28,167,000,000 29,807,000,000 29,135,000,000 26,422,000,000 25,602,000,000 27,217,000,000 27,847,000,000 25,924,000,000 27,189,000,000 26,982,000,000 26,615,000,000 25,252,000,000 26,693,000,000 26,813,000,000 27,164,000,000 27,206,000,000 29,203,000,000 28,389,000,000 28,827,000,000 31,776,000,000 30,077,000,000 30,029,000,000 30,807,000,000 30,271,000,000 28,745,000,000 30,496,000,000 29,802,000,000 23,358,000,000 23,956,000,000 22,959,000,000 21,641,000,000 24,438,000,000 23,108,000,000 20,718,000,000 24,075,000,000 26,507,000,000 23,823,000,000 24,791,000,000 24,591,000,000 28,683,000,000 30,103,000,000 28,618,000,000 
        liabilities, redeemable noncontrolling interests, and equity
                                                                         
        liabilities
                                                                         
        current liabilities
                                                                         
        accounts payable and accrued liabilities
      2,208,000,000 2,861,000,000 2,398,000,000 2,294,000,000 2,088,000,000 2,905,000,000 2,588,000,000 2,319,000,000 1,925,000,000 1,749,000,000 1,625,000,000 1,681,000,000 2,114,000,000 1,798,000,000 1,728,000,000 1,728,000,000 2,192,000,000 1,995,000,000 1,692,000,000 1,628,000,000 2,016,000,000 1,608,000,000 1,488,000,000 1,549,000,000 1,939,000,000 1,499,000,000 1,369,000,000 1,479,000,000 1,943,000,000 1,600,000,000 1,447,000,000 1,545,000,000 1,588,000,000 1,423,000,000 1,332,000,000 1,801,000,000 1,477,000,000 1,373,000,000 1,420,000,000 1,772,000,000 1,447,000,000 1,368,000,000 1,391,000,000 1,528,000,000 1,498,000,000 1,499,000,000 1,440,000,000 1,339,000,000 1,432,000,000 1,611,000,000 1,557,000,000 1,544,000,000 1,281,000,000 1,192,000,000 1,269,000,000 1,377,000,000 1,392,000,000 1,336,000,000 1,180,000,000 1,207,000,000 1,206,000,000       
        short-term debt and current portion of long-term debt
      1,121,000,000 589,000,000 1,735,000,000 1,837,000,000 1,348,000,000 751,000,000  4,000,000 606,000,000 1,282,000,000 1,338,000,000 775,000,000 945,000,000 711,000,000 739,000,000 599,000,000 1,164,000,000 150,000,000 13,000,000  448,000,000 472,000,000 782,000,000 1,884,000,000 712,000,000 1,148,000,000 844,000,000 426,000,000 251,000,000 741,000,000 799,000,000 403,000,000 305,000,000 292,000,000 667,000,000 336,000,000 250,000,000 251,000,000 695,000,000 562,000,000 1,327,000,000 1,237,000,000 966,000,000 660,000,000 799,000,000 1,077,000,000 802,000,000 392,000,000 286,000,000 163,000,000 52,000,000 502,000,000 610,000,000 370,000,000 84,000,000             
        fiduciary liabilities
      18,905,000,000 17,889,000,000 18,781,000,000 20,677,000,000 17,766,000,000 17,566,000,000 17,596,000,000 18,865,000,000 17,161,000,000 15,965,000,000 18,193,000,000 16,629,000,000 15,900,000,000 14,699,000,000 16,864,000,000 15,277,000,000 14,386,000,000 14,017,000,000 15,804,000,000 13,894,000,000 13,798,000,000 13,549,000,000 13,794,000,000 12,401,000,000 11,834,000,000 11,041,000,000 12,071,000,000 11,412,000,000 10,166,000,000 9,314,000,000 10,476,000,000 10,738,000,000 9,292,000,000 9,582,000,000 9,162,000,000 9,485,000,000 8,710,000,000 10,201,000,000 9,776,000,000 9,932,000,000 9,956,000,000 11,389,000,000 10,894,000,000 10,815,000,000 12,786,000,000 12,038,000,000 12,224,000,000 12,736,000,000 11,795,000,000 10,315,000,000 11,760,000,000 10,609,000,000 9,545,000,000 12,226,000,000 11,089,000,000 9,551,000,000 12,323,000,000 11,239,000,000 9,109,000,000 11,358,000,000        
        other current liabilities
      2,303,000,000 1,887,000,000 2,189,000,000 2,267,000,000 2,131,000,000 1,773,000,000 1,914,000,000 2,310,000,000 2,146,000,000 1,726,000,000 1,793,000,000 1,510,000,000 1,347,000,000 1,480,000,000 1,746,000,000 1,585,000,000 1,331,000,000 1,348,000,000 1,418,000,000 1,301,000,000 1,171,000,000 1,241,000,000 1,319,000,000 1,277,000,000 1,086,000,000 1,163,000,000 1,197,000,000 1,220,000,000 936,000,000 988,000,000 1,121,000,000 972,000,000 1,289,000,000 2,078,000,000 773,000,000 873,000,000 929,000,000 872,000,000 902,000,000 820,000,000 811,000,000 845,000,000 865,000,000 853,000,000 957,000,000 967,000,000 795,000,000 733,000,000 739,000,000 676,000,000 618,000,000 604,000,000 383,000,000 350,000,000 334,000,000 277,000,000 345,000,000 308,000,000 346,000,000 694,000,000 286,000,000       
        total current liabilities
      24,537,000,000 23,226,000,000 25,103,000,000 27,075,000,000 23,333,000,000 22,995,000,000 22,098,000,000 23,498,000,000 21,838,000,000 20,722,000,000 22,949,000,000 20,595,000,000 20,306,000,000 18,688,000,000 21,077,000,000 19,189,000,000 19,073,000,000 17,510,000,000 18,927,000,000 16,823,000,000 17,433,000,000 16,870,000,000 17,383,000,000 17,111,000,000 15,571,000,000 14,851,000,000 15,481,000,000 14,537,000,000 13,296,000,000 12,643,000,000 13,843,000,000 13,658,000,000 12,474,000,000 13,375,000,000 12,970,000,000 12,495,000,000 11,366,000,000 12,697,000,000 12,793,000,000 13,086,000,000 13,541,000,000 14,839,000,000 14,116,000,000 13,856,000,000 16,040,000,000 15,581,000,000 15,261,000,000 15,200,000,000 14,252,000,000 12,765,000,000 13,987,000,000 13,259,000,000 11,819,000,000 14,138,000,000 12,776,000,000 11,217,000,000 14,859,000,000 13,111,000,000 10,638,000,000 13,259,000,000 15,743,000,000       
        long-term debt
      13,542,000,000 14,660,000,000 15,055,000,000 15,451,000,000 16,284,000,000 16,265,000,000 17,090,000,000 17,610,000,000 15,916,000,000 9,969,000,000 9,989,000,000 10,577,000,000 9,825,000,000 10,116,000,000 9,666,000,000 9,685,000,000 8,228,000,000 8,250,000,000 7,272,000,000 7,263,000,000 7,281,000,000 7,251,000,000 7,229,000,000 6,227,000,000 6,627,000,000 6,120,000,000 6,740,000,000 5,990,000,000 5,993,000,000 5,665,000,000 5,659,000,000 5,697,000,000 5,662,000,000 5,631,000,000 5,610,000,000 5,869,000,000 5,910,000,000 5,907,000,000 5,902,000,000 5,175,000,000 4,799,000,000 4,824,000,000 4,710,000,000 4,840,000,000 5,155,000,000 3,669,000,000 3,770,000,000 4,098,000,000 4,168,000,000 4,415,000,000 4,479,000,000 4,409,000,000 3,146,000,000 1,601,000,000 2,013,000,000 1,998,000,000 1,249,000,000 1,848,000,000 1,964,000,000 2,022,000,000 1,995,000,000       
        non-current operating lease liabilities
      633,000,000 641,000,000 651,000,000 705,000,000 689,000,000 685,000,000 712,000,000 702,000,000 611,000,000 640,000,000 675,000,000 681,000,000 693,000,000 667,000,000 691,000,000 736,000,000 772,000,000 817,000,000 841,000,000 849,000,000 897,000,000 910,000,000 947,000,000 910,000,000 944,000,000 922,000,000 962,000,000 978,000,000                                        
        deferred tax liabilities
      350,000,000 340,000,000 361,000,000 363,000,000 384,000,000 319,000,000 1,086,000,000 1,177,000,000 129,000,000 117,000,000 120,000,000 110,000,000 99,000,000 332,000,000 364,000,000 399,000,000 401,000,000 414,000,000 417,000,000 293,000,000 262,000,000 223,000,000 200,000,000 189,000,000 199,000,000 209,000,000 211,000,000 205,000,000 181,000,000 273,000,000 294,000,000 243,000,000 83,000,000 84,000,000 112,000,000 101,000,000                                
        pension, other postretirement, and postemployment liabilities
      1,028,000,000 1,084,000,000 1,052,000,000 1,078,000,000 1,101,000,000 1,127,000,000 1,168,000,000 1,173,000,000 1,198,000,000 1,146,000,000 1,159,000,000 1,169,000,000 1,186,000,000 1,237,000,000 1,277,000,000 1,320,000,000 1,375,000,000 1,607,000,000 1,644,000,000 1,681,000,000 1,763,000,000 1,597,000,000 1,641,000,000 1,655,000,000 1,738,000,000 1,551,000,000 1,576,000,000 1,590,000,000 1,636,000,000 1,603,000,000 1,715,000,000 1,759,000,000                                    
        other non-current liabilities
      1,359,000,000 1,285,000,000 1,216,000,000 1,249,000,000 1,239,000,000 1,144,000,000 1,178,000,000 1,135,000,000 1,103,000,000 1,004,000,000 995,000,000 1,063,000,000 1,024,000,000 853,000,000 857,000,000 871,000,000 910,000,000 919,000,000 912,000,000 905,000,000 895,000,000 888,000,000 900,000,000 930,000,000 877,000,000 953,000,000 924,000,000 973,000,000 1,097,000,000 1,090,000,000 1,088,000,000 1,105,000,000 846,000,000 858,000,000 733,000,000 844,000,000 759,000,000 767,000,000 838,000,000 769,000,000 1,091,000,000 1,140,000,000 1,131,000,000 1,422,000,000 1,289,000,000 1,248,000,000 1,338,000,000 1,332,000,000 1,363,000,000 1,743,000,000 1,792,000,000 1,798,000,000 876,000,000 1,023,000,000 943,000,000 1,051,000,000 1,019,000,000 1,041,000,000 1,033,000,000 1,043,000,000 1,029,000,000       
        total liabilities
      41,449,000,000 41,236,000,000 43,438,000,000 45,921,000,000 43,030,000,000 42,535,000,000 43,332,000,000 45,295,000,000 40,795,000,000 33,598,000,000 35,887,000,000 34,195,000,000 33,133,000,000 31,893,000,000 33,932,000,000 32,200,000,000 30,759,000,000 29,517,000,000 30,013,000,000 27,814,000,000 28,531,000,000 27,739,000,000 28,300,000,000 27,022,000,000 25,956,000,000 24,606,000,000 25,894,000,000 24,273,000,000 22,203,000,000 21,274,000,000 22,599,000,000 22,462,000,000 20,677,000,000 21,636,000,000 21,156,000,000 21,083,000,000 19,758,000,000 21,132,000,000 21,466,000,000 21,001,000,000 21,264,000,000 22,747,000,000 21,958,000,000 21,555,000,000 24,017,000,000 22,071,000,000 22,396,000,000 22,597,000,000 21,855,000,000 20,466,000,000 22,031,000,000 21,315,000,000 17,514,000,000 18,478,000,000 17,502,000,000 15,511,000,000 18,430,000,000 17,446,000,000 14,771,000,000 17,620,000,000 20,055,000,000 18,208,000,000 19,447,000,000 19,331,000,000 23,311,000,000 24,711,000,000 23,310,000,000 
        redeemable noncontrolling interests
      22,000,000 89,000,000 85,000,000 81,000,000 79,000,000 125,000,000 135,000,000 130,000,000                                                            
        equity
                                                                         
        ordinary shares - 0.01 nominal value authorized: 500.0 shares
      2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000                                                  
        additional paid-in capital
      13,453,000,000 13,438,000,000 13,379,000,000 13,258,000,000 13,198,000,000 13,173,000,000 13,045,000,000 12,910,000,000 6,969,000,000 7,015,000,000 6,906,000,000 6,860,000,000 6,864,000,000 6,772,000,000 6,669,000,000 6,627,000,000 6,624,000,000 6,529,000,000 6,381,000,000 6,348,000,000 6,312,000,000 6,216,000,000 6,144,000,000 6,121,000,000 6,152,000,000 6,084,000,000 6,002,000,000 5,958,000,000 5,965,000,000 5,850,000,000 5,772,000,000 5,743,000,000 5,670,000,000 5,587,000,000 5,567,000,000 5,577,000,000 5,522,000,000 5,434,000,000 5,388,000,000 5,409,000,000 5,318,000,000 5,226,000,000 5,177,000,000 5,012,000,000 4,933,000,000 4,860,000,000 4,507,000,000 4,279,000,000 3,913,000,000 3,975,000,000 3,946,000,000 3,942,000,000 3,135,000,000 3,134,000,000 3,135,000,000 3,166,000,000 3,160,000,000 3,129,000,000 3,153,000,000 3,107,000,000 3,066,000,000 2,741,000,000 2,704,000,000 2,619,000,000 2,463,000,000   
        retained earnings
      307,000,000                -1,694,000,000 -445,000,000 1,823,000,000 1,801,000,000 1,042,000,000 1,423,000,000 1,751,000,000 1,455,000,000 1,254,000,000 1,436,000,000 1,669,000,000 2,555,000,000 2,093,000,000 2,042,000,000 2,295,000,000 2,747,000,000 2,914,000,000 3,574,000,000 3,934,000,000 3,807,000,000 3,702,000,000 3,784,000,000 3,600,000,000 4,117,000,000 4,015,000,000 4,405,000,000 4,612,000,000 4,718,000,000 4,982,000,000 5,403,000,000 5,844,000,000 6,302,000,000 8,770,000,000 8,377,000,000 8,233,000,000 8,039,000,000 7,700,000,000 7,605,000,000 7,500,000,000 7,189,000,000 7,132,000,000 7,034,000,000 6,868,000,000 6,807,000,000 5,767,000,000 5,452,000,000 5,303,000,000 5,141,000,000 4,897,000,000 4,843,000,000 4,711,000,000 
        accumulated other comprehensive loss
      -3,928,000,000 -3,843,000,000 -3,915,000,000 -3,843,000,000 -4,456,000,000 -4,745,000,000 -4,121,000,000 -4,478,000,000 -4,404,000,000 -4,579,000,000 -4,338,000,000 -4,544,000,000 -4,623,000,000 -4,919,000,000 -4,260,000,000 -3,843,000,000 -3,871,000,000 -3,877,000,000 -3,744,000,000 -3,891,000,000 -3,861,000,000 -4,099,000,000 -4,296,000,000 -4,409,000,000 -4,033,000,000 -4,030,000,000 -3,837,000,000 -3,740,000,000 -3,909,000,000 -3,632,000,000 -3,524,000,000 -3,191,000,000 -3,412,000,000 -3,677,000,000 -3,750,000,000 -3,912,000,000 -3,793,000,000 -3,722,000,000 -3,710,000,000 -3,423,000,000 -3,453,000,000 -3,236,000,000 -3,427,000,000 -2,518,000,000 -2,218,000,000 -2,320,000,000 -2,775,000,000                     
        total aon shareholders' equity
      9,834,000,000 9,352,000,000 7,939,000,000 7,843,000,000 7,004,000,000 6,121,000,000 6,244,000,000 5,860,000,000   65,000,000  -529,000,000 -783,000,000 684,000,000 1,177,000,000 1,061,000,000 2,209,000,000 4,462,000,000 4,260,000,000 3,495,000,000 3,542,000,000 3,601,000,000 3,169,000,000 3,375,000,000 3,492,000,000 3,836,000,000 4,775,000,000 4,151,000,000 4,262,000,000 4,545,000,000 5,301,000,000 5,175,000,000 5,487,000,000 5,754,000,000 5,475,000,000 5,434,000,000 5,499,000,000 5,281,000,000 6,106,000,000 5,883,000,000 6,398,000,000 6,365,000,000 7,215,000,000                        
        nonredeemable noncontrolling interests
      124,000,000 107,000,000 175,000,000 165,000,000 191,000,000 184,000,000 174,000,000 168,000,000                                                            
        total equity
      9,958,000,000 9,459,000,000 8,114,000,000 8,008,000,000 7,195,000,000 6,305,000,000 6,418,000,000 6,028,000,000   162,000,000 58,000,000 -429,000,000 -670,000,000 788,000,000 1,291,000,000 1,158,000,000 2,299,000,000 4,567,000,000 4,361,000,000 3,583,000,000 3,620,000,000 3,695,000,000 3,260,000,000 3,449,000,000 3,561,000,000 3,913,000,000 4,862,000,000 4,219,000,000 4,328,000,000 4,618,000,000 5,385,000,000 5,247,000,000 5,553,000,000 5,826,000,000 5,532,000,000 5,494,000,000 5,561,000,000 5,347,000,000 6,163,000,000 5,942,000,000 6,456,000,000 6,431,000,000 7,272,000,000 7,759,000,000 8,006,000,000 7,633,000,000 8,210,000,000 8,416,000,000 8,279,000,000 8,465,000,000 8,487,000,000 5,844,000,000 5,478,000,000 5,457,000,000 6,130,000,000 6,008,000,000 5,662,000,000          
        total liabilities, redeemable noncontrolling interests and equity
      51,429,000,000  51,637,000,000 54,010,000,000 50,304,000,000  49,885,000,000 51,453,000,000                                                            
        accumulated deficit
       -245,000,000 -1,527,000,000 -1,574,000,000 -1,740,000,000 -2,309,000,000 -2,682,000,000 -2,574,000,000 -2,700,000,000 -3,024,000,000 -2,505,000,000 -2,388,000,000 -2,772,000,000 -2,638,000,000 -1,727,000,000 -1,609,000,000                                                    
        total liabilities, redeemable noncontrolling interests, and equity
       50,784,000,000    48,965,000,000                                                              
        liabilities and equity
                                                                         
        total aon shareholders' deficit
              -133,000,000 -586,000,000  -70,000,000                                                        
        noncontrolling interests
              105,000,000 100,000,000 97,000,000 128,000,000 100,000,000 113,000,000 104,000,000 114,000,000 97,000,000 90,000,000 105,000,000 101,000,000 88,000,000 78,000,000 94,000,000 91,000,000 74,000,000 69,000,000 77,000,000 87,000,000 68,000,000 66,000,000 73,000,000 84,000,000 72,000,000 66,000,000 72,000,000 57,000,000 60,000,000 62,000,000 66,000,000 57,000,000 59,000,000 58,000,000 66,000,000 57,000,000 59,000,000 60,000,000 54,000,000 58,000,000 58,000,000 46,000,000 67,000,000 64,000,000 52,000,000 50,000,000 55,000,000 140,000,000 142,000,000 109,000,000          
        total deficit
              -28,000,000 -486,000,000                                                          
        total liabilities and equity
              40,767,000,000 33,112,000,000 36,049,000,000 34,253,000,000 32,704,000,000 31,223,000,000 34,720,000,000 33,491,000,000 31,917,000,000 31,816,000,000 34,580,000,000 32,175,000,000 32,114,000,000 31,359,000,000 31,995,000,000 30,282,000,000 29,405,000,000 28,167,000,000 29,807,000,000 29,135,000,000 26,422,000,000 25,602,000,000 27,217,000,000 27,847,000,000 25,924,000,000 27,189,000,000 26,982,000,000 26,615,000,000 25,252,000,000 26,693,000,000 26,813,000,000 27,164,000,000 27,206,000,000 29,203,000,000 28,389,000,000 28,827,000,000 31,776,000,000 30,077,000,000 30,029,000,000 30,807,000,000 30,271,000,000 28,745,000,000 30,496,000,000 29,802,000,000 23,358,000,000 23,956,000,000 22,959,000,000 21,641,000,000 24,438,000,000 23,108,000,000          
        ordinary shares - 0.01 nominal value authorized: 500 shares
                        2,000,000 2,000,000  2,000,000 2,000,000                                             
        ordinary shares - 0.01 nominal value authorized: 2020 - 500 shares; 2019 - 750 shares
                          2,000,000                                               
        ordinary shares - 0.01 nominal value authorized: 750 shares
                             2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 2,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000 3,000,000                     
        current assets of discontinued operations
                                        3,186,000,000                                 
        non-current assets of discontinued operations
                                                                         
        current liabilities of discontinued operations
                                        1,036,000,000                                 
        pension, other postretirement and postemployment liabilities
                                      1,612,000,000 1,688,000,000 1,731,000,000                                 
        non-current liabilities of discontinued operations
                                                                         
        pension, other post retirement, and post employment liabilities
                                         1,774,000,000    1,795,000,000         2,072,000,000                   
        non-current deferred tax assets
                                          278,000,000 265,000,000 171,000,000 141,000,000                            
        non-current deferred tax liabilities
                                          36,000,000 39,000,000 177,000,000 176,000,000                            
        pension, other post-retirement and post-employment liabilities
                                          1,687,000,000 1,722,000,000 1,756,000,000  1,833,000,000 1,944,000,000 2,001,000,000                         
        investments
                                                 143,000,000 138,000,000 143,000,000 152,000,000 200,000,000 211,000,000 254,000,000 249,000,000 318,000,000 301,000,000 301,000,000 308,000,000 297,000,000 296,000,000 313,000,000          
        pension, other post-retirement and other post-employment liabilities
                                                 1,437,000,000 1,533,000,000 1,573,000,000 2,027,000,000                     
        total aon shareholders’ equity
                                                  7,700,000,000 7,946,000,000 7,579,000,000 8,152,000,000                    
        pension and other post employment liabilities
                                                     1,967,000,000  1,543,000,000 1,773,000,000 1,849,000,000 1,673,000,000 1,716,000,000 1,770,000,000 1,245,000,000 1,303,000,000 1,446,000,000          
        ordinary shares
                                                     3,000,000                    
        treasury shares at cost
                                                                         
        common stock-1 par value
                                                      386,000,000          361,000,000 361,000,000 361,000,000       
        authorized: 750 shares
                                                       386,000,000 386,000,000 386,000,000 363,000,000   363,000,000            
        treasury stock
                                                                         
        total aon stockholders’ equity
                                                      8,358,000,000 8,233,000,000 8,398,000,000 8,423,000,000 5,792,000,000 5,428,000,000 5,402,000,000 5,990,000,000 5,866,000,000 5,553,000,000          
        common stock-1 par value authorized: 750 shares
                                                           363,000,000 363,000,000  363,000,000 363,000,000          
        current liabilities:
                                                                         
        current assets:
                                                                         
        assets held for sale
                                                              189,000,000 188,000,000 31,000,000  4,446,000,000    4,672,000,000 3,998,000,000  
        other intangible assets
                                                             763,000,000 776,000,000 738,000,000 222,000,000 245,000,000 239,000,000 203,000,000 202,000,000 197,000,000 136,000,000 136,000,000 110,000,000 
        short-term debt
                                                             12,000,000 681,000,000 104,000,000   84,000,000       
        liabilities held for sale
                                                              118,000,000 124,000,000 3,000,000  2,978,000,000    3,976,000,000 3,356,000,000  
        aon stockholders’ equity:
                                                                         
        stockholders’ equity:
                                                                         
        cash
                                                                478,000,000 466,000,000 452,000,000 321,000,000 406,000,000 351,000,000 461,000,000 425,000,000 451,000,000 
        long-term investments
                                                                370,000,000 414,000,000 416,000,000       
        liabilities and stockholders’ equity
                                                                         
        pension, post employment and post retirement liabilities
                                                                1,136,000,000 1,296,000,000 1,288,000,000       
        stockholders’ equity
                                                                         
        total stockholders’ equity
                                                                5,947,000,000 6,455,000,000 6,452,000,000  5,344,000,000 5,260,000,000 5,372,000,000 5,392,000,000 5,308,000,000 
        total liabilities and stockholders’ equity
                                                                20,718,000,000 24,075,000,000 26,507,000,000  24,791,000,000 24,591,000,000 28,683,000,000 30,103,000,000 28,618,000,000 
        net fiduciary assets
                                                                  11,189,000,000       
        net fiduciary liabilities
                                                                  11,189,000,000       
        fixed maturities at fair value
                                                                   2,970,000,000 2,920,000,000 2,888,000,000 2,962,000,000 2,802,000,000 4,152,000,000 
        equity securities at fair value
                                                                   39,000,000 39,000,000 58,000,000 66,000,000 48,000,000 47,000,000 
        other investments
                                                                   380,000,000 389,000,000 406,000,000 397,000,000 400,000,000 400,000,000 
        total investments
                                                                   7,485,000,000 7,547,000,000 7,666,000,000 7,072,000,000 7,386,000,000 9,301,000,000 
        risk and insurance brokerage services and consulting
                                                                   7,995,000,000 8,951,000,000 8,624,000,000 8,062,000,000 9,427,000,000 8,414,000,000 
        other receivables
                                                                   301,000,000 304,000,000 348,000,000 845,000,000 1,143,000,000 1,549,000,000 
        total receivables
                                                                   8,296,000,000 9,255,000,000 8,972,000,000 8,907,000,000 10,570,000,000 9,963,000,000 
        deferred policy acquisition costs
                                                                   576,000,000 562,000,000 544,000,000 524,000,000 538,000,000 1,230,000,000 
        property and equipment
                                                                   520,000,000 526,000,000 507,000,000 499,000,000 507,000,000 524,000,000 
        other assets
                                                                   1,539,000,000 1,554,000,000 1,656,000,000 2,002,000,000 2,153,000,000 2,616,000,000 
        liabilities and stockholders' equity
                                                                         
        insurance premiums payable
                                                                   9,457,000,000 10,581,000,000 10,410,000,000 9,332,000,000 10,976,000,000 10,165,000,000 
        policy liabilities
                                                                         
        future policy benefits
                                                                   1,909,000,000 1,863,000,000 1,812,000,000 1,764,000,000 1,731,000,000 1,695,000,000 
        policy and contract claims
                                                                   644,000,000 640,000,000 647,000,000 1,468,000,000 1,619,000,000 1,848,000,000 
        unearned and advance premiums
                                                                   337,000,000 409,000,000 410,000,000    
        other policyholder funds
                                                                   29,000,000 27,000,000 26,000,000 23,000,000 23,000,000 22,000,000 
        total policy liabilities
                                                                   2,919,000,000 2,939,000,000 2,895,000,000 3,619,000,000 3,871,000,000 6,629,000,000 
        general liabilities
                                                                         
        general expenses
                                                                   1,553,000,000 1,483,000,000 1,585,000,000 1,544,000,000 1,504,000,000 1,694,000,000 
        short-term borrowings
                                                                   14,000,000 4,000,000 1,000,000 268,000,000 21,000,000 4,000,000 
        notes payable
                                                                   1,994,000,000 2,182,000,000 2,072,000,000 2,075,000,000 2,082,000,000 2,012,000,000 
        pension, post-employment and post-retirement liabilities
                                                                   1,436,000,000 1,430,000,000 1,407,000,000 1,734,000,000 1,646,000,000 1,545,000,000 
        other liabilities
                                                                   835,000,000 828,000,000 961,000,000 763,000,000 1,255,000,000 1,261,000,000 
        stockholders' equity
                                                                         
        common stock - 1 par value
                                                                   350,000,000 350,000,000 347,000,000 347,000,000 347,000,000 346,000,000 
        total stockholders' equity
                                                                   5,615,000,000      
        total liabilities and stockholders' equity
                                                                   23,823,000,000      
        unearned and advance premiums and contract fees
                                                                      364,000,000 498,000,000 3,064,000,000 
        less - treasury stock at cost
                                                                         
        paid-in additional capital
                                                                       2,436,000,000 2,412,000,000 
      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 2023-09-30 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 2019-12-31 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 2014-09-30 2014-06-30 2014-03-31 2013-03-31 2012-06-30 2012-03-31 2011-09-30 2011-06-30 2011-03-31 2010-09-30 2010-06-30 2010-03-31 2009-09-30 2009-06-30 2009-03-31 2008-09-30 2008-06-30 2008-03-31 2007-09-30 2007-06-30 2007-03-31 2006-09-30 2006-06-30 2006-03-31 
                                                                           
          cash flows from operating activities
                                                                           
          net income
        1,239,000,000 1,704,000,000 470,000,000 594,000,000 982,000,000 734,000,000 355,000,000 538,000,000 1,093,000,000 467,000,000 575,000,000 1,079,000,000 666,000,000 418,000,000 514,000,000 1,048,000,000 873,000,000 -891,000,000 393,000,000 933,000,000 534,000,000 282,000,000 411,000,000 791,000,000 382,000,000 228,000,000 287,000,000 676,000,000 353,000,000 153,000,000 58,000,000 610,000,000 192,000,000 778,000,000 305,000,000 509,000,000 314,000,000 280,000,000 327,000,000 590,000,000 303,000,000 188,000,000 341,000,000 315,000,000 313,000,000 336,000,000 272,000,000 254,000,000 249,000,000 208,000,000 267,000,000 255,000,000 147,000,000 158,000,000 186,000,000 134,000,000 155,000,000 285,000,000 117,000,000 1,133,000,000 218,000,000 204,000,000 240,000,000 213,000,000 106,000,000 193,000,000 198,000,000 
          adjustments to reconcile net income to cash from operating activities:
                                                                           
          gain from sales of businesses
        -20,000,000 -1,200,000,000    -4,000,000 -76,000,000      -1,000,000 -6,000,000 -22,000,000 -25,000,000  -1,000,000                                                  
          depreciation of fixed assets
        46,000,000 48,000,000 47,000,000 47,000,000 46,000,000 47,000,000 47,000,000 45,000,000 44,000,000 42,000,000 39,000,000 38,000,000 36,000,000 37,000,000 40,000,000 38,000,000 41,000,000 56,000,000 41,000,000 41,000,000 43,000,000 42,000,000 41,000,000 41,000,000 48,000,000 44,000,000 40,000,000 40,000,000 50,000,000 40,000,000 47,000,000 39,000,000 40,000,000 54,000,000 54,000,000 61,000,000 57,000,000 58,000,000 56,000,000 60,000,000 56,000,000 57,000,000 56,000,000 61,000,000 62,000,000 60,000,000 59,000,000 57,000,000 55,000,000 53,000,000 58,000,000 53,000,000 31,000,000               
          amortization and impairment of intangible assets
        152,000,000 185,000,000 193,000,000 201,000,000 199,000,000 185,000,000 174,000,000 128,000,000 16,000,000 20,000,000 25,000,000 25,000,000 26,000,000 34,000,000 25,000,000 28,000,000 35,000,000 36,000,000 36,000,000 40,000,000 41,000,000 50,000,000 58,000,000 97,000,000 97,000,000 101,000,000 97,000,000 97,000,000 101,000,000 100,000,000 282,000,000 110,000,000 101,000,000                                   
          share-based compensation expense
        82,000,000 60,000,000 106,000,000 119,000,000 147,000,000 113,000,000 114,000,000 117,000,000 130,000,000 95,000,000 99,000,000 127,000,000 93,000,000 93,000,000 92,000,000 119,000,000 103,000,000 130,000,000 85,000,000 131,000,000 105,000,000 67,000,000 64,000,000 76,000,000 65,000,000 72,000,000 91,000,000 89,000,000 124,000,000 67,000,000 70,000,000 77,000,000 66,000,000 70,000,000 78,000,000 103,000,000 73,000,000 70,000,000 85,000,000 101,000,000 75,000,000 74,000,000 90,000,000 72,000,000 73,000,000 102,000,000 69,000,000                     
          deferred income taxes
        -49,000,000 95,000,000 6,000,000 -125,000,000 -117,000,000 -165,000,000 -24,000,000 -46,000,000 -76,000,000 -64,000,000 -98,000,000 -70,000,000 -165,000,000 -51,000,000 -18,000,000 -18,000,000 -72,000,000 -32,000,000 96,000,000 19,000,000 13,000,000 11,000,000 -9,000,000 -6,000,000 8,000,000 -19,000,000 -25,000,000 -97,000,000 -35,000,000 -119,000,000 26,000,000 19,000,000 -225,000,000 -2,000,000 -17,000,000 -22,000,000 -8,000,000 23,000,000 -140,000,000 -99,000,000 9,000,000 7,000,000 59,000,000 8,000,000 10,000,000 13,000,000 7,000,000 16,000,000 -14,000,000 6,000,000 11,000,000    78,000,000 -11,000,000 14,000,000          
          other
        1,000,000 -17,000,000 -5,000,000 -94,000,000 -17,000,000 -8,000,000 -14,000,000 -30,000,000 -82,000,000                                                          
          change in assets and liabilities:
                                                                           
          receivables
        -905,000,000 85,000,000 560,000,000 -160,000,000 -742,000,000 72,000,000 575,000,000 -133,000,000 -826,000,000 414,000,000 -40,000,000 -664,000,000 50,000,000 528,000,000 -130,000,000 -544,000,000 -40,000,000 398,000,000 8,000,000 -485,000,000 -85,000,000 455,000,000 281,000,000 -543,000,000 -204,000,000 310,000,000 -19,000,000 -458,000,000 -116,000,000 360,000,000 -102,000,000 -269,000,000 169,000,000 -63,000,000 38,000,000 -375,000,000 114,000,000 65,000,000 110,000,000 -315,000,000 173,000,000 10,000,000 49,000,000 105,000,000 102,000,000 13,000,000 174,000,000 20,000,000 61,000,000   108,000,000  -43,000,000 45,000,000             
          accounts payable and accrued liabilities
        -656,000,000 388,000,000 195,000,000 108,000,000 -846,000,000 429,000,000 215,000,000 92,000,000 -343,000,000 158,000,000 -72,000,000 -443,000,000 233,000,000 153,000,000 41,000,000 -449,000,000 242,000,000 317,000,000 61,000,000 -356,000,000 377,000,000 132,000,000 -48,000,000 -275,000,000 357,000,000 194,000,000 -125,000,000 -454,000,000 356,000,000 164,000,000 -56,000,000 -439,000,000 140,000,000 13,000,000 -390,000,000 341,000,000 112,000,000 -41,000,000 -348,000,000 502,000,000 122,000,000 -71,000,000 -466,000,000 84,000,000 -24,000,000 -468,000,000 -417,000,000                     
          accelerating aon united program liabilities
        14,000,000 56,000,000 -44,000,000 21,000,000 -6,000,000 -26,000,000 -18,000,000 27,000,000 34,000,000                                                           
          current income taxes
        243,000,000 255,000,000 -68,000,000 -225,000,000 152,000,000  -179,000,000 -103,000,000 163,000,000 5,000,000 -73,000,000 126,000,000 80,000,000 -1,000,000 -16,000,000 153,000,000 153,000,000 -36,000,000 -59,000,000 142,000,000 -51,000,000 -152,000,000 45,000,000 141,000,000 -23,000,000 -7,000,000 -108,000,000 118,000,000 171,000,000 7,000,000 -174,000,000 30,000,000 -760,000,000 31,000,000 -56,000,000 78,000,000 6,000,000 -4,000,000 -31,000,000 185,000,000 83,000,000 -179,000,000 27,000,000 -66,000,000 -147,000,000 2,000,000 -65,000,000 7,000,000 41,000,000 50,000,000 64,000,000 58,000,000  -19,000,000 65,000,000             
          pension, other postretirement and postemployment liabilities
        -14,000,000 1,000,000 -5,000,000 -4,000,000 -8,000,000 7,000,000 -8,000,000 -5,000,000 -12,000,000 6,000,000 6,000,000 -9,000,000 -9,000,000 -8,000,000 -9,000,000 -27,000,000 -18,000,000 -21,000,000 -21,000,000 -59,000,000 -24,000,000 -55,000,000 -21,000,000 -41,000,000 -29,000,000 -35,000,000 -38,000,000 -54,000,000  -139,000,000                                      
          other assets and liabilities
        297,000,000 -263,000,000 -306,000,000 314,000,000 350,000,000 -303,000,000 -148,000,000 140,000,000 168,000,000 -100,000,000 199,000,000 234,000,000 -137,000,000 -151,000,000 151,000,000 140,000,000 -246,000,000 -50,000,000 145,000,000 155,000,000 -178,000,000 3,000,000 82,000,000 141,000,000 -89,000,000 -42,000,000 58,000,000 74,000,000 -137,000,000 -162,000,000 263,000,000 38,000,000 -69,000,000 -62,000,000 92,000,000 -33,000,000 27,000,000 -13,000,000 69,000,000 -29,000,000 3,000,000 125,000,000 50,000,000 -51,000,000 -7,000,000 21,000,000 62,000,000                     
          cash from operating activities
        430,000,000 1,397,000,000 1,148,000,000 796,000,000 140,000,000 1,200,000,000 1,013,000,000 513,000,000 309,000,000 1,043,000,000 688,000,000 443,000,000 1,042,000,000 1,046,000,000 668,000,000 463,000,000 931,000,000 -94,000,000 784,000,000 561,000,000 760,000,000 804,000,000 881,000,000 338,000,000 672,000,000 802,000,000 287,000,000 74,000,000 711,000,000 562,000,000 273,000,000 140,000,000 -147,000,000 260,000,000 240,000,000 851,000,000 711,000,000 491,000,000 273,000,000 934,000,000 710,000,000 229,000,000 136,000,000 550,000,000 344,000,000 -11,000,000    252,000,000 579,000,000 582,000,000 -99,000,000 408,000,000 464,000,000 84,000,000 -456,000,000 553,000,000   516,000,000   816,000,000 -68,000,000   
          cash flows from investing activities
                                                                           
          proceeds from investments
        17,000,000 31,000,000 43,000,000 51,000,000 20,000,000 26,000,000 40,000,000 28,000,000 118,000,000 5,000,000 41,000,000 13,000,000 39,000,000 6,000,000 20,000,000 45,000,000 7,000,000 10,000,000 30,000,000 11,000,000 30,000,000 17,000,000 11,000,000 6,000,000 28,000,000 19,000,000 2,000,000 12,000,000 41,000,000 7,000,000 6,000,000 17,000,000 14,000,000 4,000,000 25,000,000 12,000,000 8,000,000 10,000,000 13,000,000                             
          purchases of investments
        -19,000,000 -33,000,000 -97,000,000 -23,000,000 -19,000,000 -36,000,000 -45,000,000 -35,000,000 -56,000,000 -32,000,000 -18,000,000 -11,000,000                       -9,000,000  -18,000,000 -15,000,000 -14,000,000                             
          net sale (purchases) of short-term investments - non fiduciary
        1,363,000,000                                                                   
          acquisition of businesses, net of cash and funds held on behalf of clients
        -296,000,000 -118,000,000 -133,000,000 -27,000,000 -116,000,000 -495,000,000 -231,000,000 -2,776,000,000 -4,000,000 -10,000,000 -6,000,000 -2,000,000 -8,000,000 -11,000,000 -9,000,000 -134,000,000                                                    
          sale of businesses, net of cash and funds held on behalf of clients
        1,000,000 2,237,000,000 -7,000,000 95,000,000 24,000,000 14,000,000 334,000,000 277,000,000 75,000,000 1,000,000 1,000,000 58,000,000 22,000,000                                                    
          capital expenditures
        -67,000,000 -74,000,000 -69,000,000 -64,000,000 -56,000,000 -55,000,000 -62,000,000 -53,000,000 -48,000,000 -58,000,000 -69,000,000 -76,000,000 -70,000,000 -58,000,000 -45,000,000 -23,000,000 -35,000,000 -32,000,000 -41,000,000 -29,000,000 -22,000,000 -30,000,000 -30,000,000 -59,000,000 -58,000,000 -61,000,000 -49,000,000 -57,000,000 -61,000,000 -68,000,000 -66,000,000 -45,000,000 -43,000,000 -48,000,000 -34,000,000 -69,000,000 -49,000,000 -52,000,000 -52,000,000 -65,000,000 -83,000,000 -80,000,000 -62,000,000 -64,000,000 -60,000,000 -55,000,000          
          free cash flows
        363,000,000 1,323,000,000 1,079,000,000 732,000,000 84,000,000 1,145,000,000 951,000,000 460,000,000 261,000,000 985,000,000 619,000,000 367,000,000 972,000,000 988,000,000 623,000,000 440,000,000 896,000,000 -126,000,000 743,000,000 532,000,000 738,000,000 774,000,000 851,000,000 279,000,000 614,000,000 741,000,000 238,000,000 17,000,000 650,000,000 494,000,000 207,000,000 95,000,000 -190,000,000 212,000,000 206,000,000 782,000,000 662,000,000 439,000,000 221,000,000 869,000,000 627,000,000 149,000,000 74,000,000 486,000,000 284,000,000 -66,000,000    252,000,000 579,000,000 582,000,000 -99,000,000 408,000,000 464,000,000 84,000,000 -456,000,000 553,000,000   516,000,000   816,000,000 -68,000,000   
          cash from investing activities
        999,000,000 648,000,000 -94,000,000 24,000,000 -292,000,000 -577,000,000 29,000,000 2,676,000,000 -4,961,000,000 -76,000,000 -77,000,000 205,000,000 -240,000,000 -84,000,000 138,000,000 -263,000,000 165,000,000 -89,000,000 -129,000,000 102,000,000 136,000,000 177,000,000 -554,000,000 -438,000,000 2,000,000 -9,000,000 -195,000,000 -27,000,000 -53,000,000 -95,000,000 -167,000,000 346,000,000 1,033,000,000 1,476,000,000 13,000,000 -583,000,000 -287,000,000 115,000,000 -199,000,000 48,000,000 15,000,000 -203,000,000 2,000,000 -316,000,000 -102,000,000 156,000,000 -62,000,000 -129,000,000 222,000,000       16,000,000            
          cash flows from financing activities
                                                                           
          share repurchase
        -500,000,000 -250,000,000 -250,000,000 -250,000,000 -250,000,000 -200,000,000 -300,000,000 -250,000,000 -250,000,000 -850,000,000 -550,000,000 -550,000,000 -675,000,000 -1,200,000,000 -500,000,000 -828,000,000 -2,000,000,000 -1,251,000,000 -242,000,000 -50,000,000 -800,000,000 -500,000,000 -463,000,000 -453,000,000 -352,000,000 -1,055,000,000 -100,000,000 -198,000,000 -301,000,000 -402,000,000 -569,000,000 -788,000,000 -974,000,000 -126,000,000 -220,000,000 -287,000,000 -65,000,000 -685,000,000 -400,000,000 -600,000,000 -300,000,000 -250,000,000 -500,000,000 -650,000,000 -600,000,000 -300,000,000                     
          proceeds from issuance of shares
        25,000,000 10,000,000 27,000,000 3,000,000 30,000,000 18,000,000 34,000,000 2,000,000 25,000,000 30,000,000 8,000,000 25,000,000                                                        
          cash paid for employee taxes on withholding shares
        -93,000,000 -7,000,000 -7,000,000 -53,000,000 -141,000,000 -12,000,000 -14,000,000 -46,000,000 -130,000,000 -16,000,000 -59,000,000 -157,000,000                                                        
          commercial paper issuances, net of repayments
         -400,000,000 -104,000,000 -114,000,000 594,000,000 -591,000,000 -57,000,000 -44,000,000 -173,000,000 360,000,000 -16,000,000                                                      
          repayment of debt
        -593,000,000 -1,150,000,000 -400,000,000   -50,000,000 -550,000,000         -2,208,000,000 -1,784,000,000 -936,000,000 -850,000,000 -650,000,000 -25,000,000 -310,000,000 -2,206,000,000 -1,341,000,000 -1,083,000,000 -1,630,000,000 -1,534,000,000 -694,000,000 -1,919,000,000 -1,471,000,000 -1,323,000,000 -704,000,000 -8,000,000 -1,040,000,000 -950,000,000 -637,000,000 -676,000,000 -1,457,000,000 -175,000,000 -2,238,000,000 -964,000,000 -1,210,000,000 -686,000,000 -1,328,000,000 -916,000,000 -829,000,000 -715,000,000                     
          increase in fiduciary liabilities, net of fiduciary receivables
        955,000,000 -1,072,000,000 137,000,000 924,000,000 -355,000,000 -329,000,000 326,000,000 -111,000,000 394,000,000 -129,000,000 363,000,000 636,000,000 -498,000,000 539,000,000 14,000,000 647,000,000                                                    
          cash dividends to shareholders
        -162,000,000 -161,000,000 -160,000,000 -161,000,000 -147,000,000 -146,000,000 -147,000,000 -146,000,000 -123,000,000 -125,000,000 -126,000,000 -115,000,000 -116,000,000 -118,000,000 -119,000,000 -110,000,000 -112,000,000 -116,000,000 -115,000,000 -104,000,000 -105,000,000 -103,000,000 -102,000,000 -102,000,000 -103,000,000 -104,000,000 -107,000,000 -96,000,000 -97,000,000 -98,000,000 -98,000,000 -89,000,000 -92,000,000 -95,000,000 -87,000,000 -87,000,000 -89,000,000 -87,000,000 -82,000,000 -83,000,000 -84,000,000 -85,000,000 -71,000,000 -73,000,000 -75,000,000 -53,000,000 -50,000,000                     
          redeemable and nonredeemable noncontrolling interests, and other financing activities
        -73,000,000 -34,000,000 -11,000,000 -73,000,000 -80,000,000                                                               
          cash from financing activities
        -441,000,000 -3,064,000,000 -768,000,000 -24,000,000 -349,000,000 -769,000,000 -699,000,000 -2,997,000,000 5,261,000,000 -1,162,000,000 -443,000,000 404,000,000 -1,451,000,000 -302,000,000 -537,000,000 500,000,000 -544,000,000 -258,000,000 -413,000,000 -709,000,000 -942,000,000 -942,000,000 -286,000,000 82,000,000 -525,000,000 -736,000,000 -92,000,000 -140,000,000 -444,000,000 -457,000,000 -135,000,000 -663,000,000 -878,000,000 -1,512,000,000 -258,000,000 -271,000,000 -371,000,000 -640,000,000 -4,000,000 -979,000,000 -582,000,000 -33,000,000 -95,000,000 -254,000,000 -189,000,000 -260,000,000 120,000,000     34,000,000   17,000,000   13,000,000          
          effect of exchange rates on cash and cash equivalents and funds held on behalf of clients
        -97,000,000 72,000,000 -90,000,000 500,000,000 196,000,000 -564,000,000 379,000,000 -56,000,000 -146,000,000 -260,000,000 145,000,000 58,000,000 530,000,000 -656,000,000 -373,000,000 -50,000,000                                                    
          net increase in cash and cash equivalents and funds held on behalf of clients
        891,000,000 -947,000,000 196,000,000 1,296,000,000 -305,000,000 -710,000,000 722,000,000 136,000,000 463,000,000 -455,000,000 313,000,000 1,110,000,000 -119,000,000 4,000,000 -104,000,000 650,000,000                                                    
          cash, cash equivalents and funds held on behalf of clients at beginning of period
        8,573,000,000  8,333,000,000  7,722,000,000 7,076,000,000  6,645,000,000                                                    
          cash, cash equivalents and funds held on behalf of clients at end of period
        9,464,000,000  196,000,000 1,296,000,000 8,028,000,000  722,000,000 136,000,000 8,185,000,000 -455,000,000 313,000,000 8,186,000,000  4,000,000 -104,000,000 7,295,000,000                                                    
          reconciliation of cash and cash equivalents and funds held on behalf of clients:
                                                                           
          cash and cash equivalents
        1,178,000,000 100,000,000 87,000,000 44,000,000 964,000,000 -18,000,000 129,000,000 -21,000,000 995,000,000 -144,000,000 -167,000,000 1,119,000,000 -2,000,000 -48,000,000 145,000,000 595,000,000                                                    
          cash and cash equivalents and funds held on behalf of clients classified as held for sale
          33,000,000 -1,000,000 2,000,000   -35,000,000 73,000,000                                                           
          funds held on behalf of clients
        8,286,000,000 -1,013,000,000 76,000,000 1,253,000,000 7,062,000,000 -693,000,000 631,000,000 192,000,000 7,117,000,000 -308,000,000 471,000,000 7,067,000,000 -117,000,000 52,000,000 -249,000,000 6,700,000,000                                                    
          total cash and cash equivalents and funds held on behalf of clients
        9,464,000,000 -947,000,000 196,000,000 1,296,000,000 8,028,000,000 -710,000,000 722,000,000 136,000,000 8,185,000,000 -455,000,000 313,000,000 8,186,000,000 -119,000,000 4,000,000 -104,000,000 7,295,000,000                                                    
          supplemental disclosures:
                                                                           
          interest paid
        271,000,000  273,000,000 143,000,000 273,000,000 120,000,000 282,000,000 161,000,000 95,000,000 89,000,000 141,000,000 79,000,000 132,000,000 64,000,000 133,000,000 22,000,000 135,000,000 31,000,000 126,000,000 36,000,000 112,000,000 38,000,000 125,000,000 51,000,000 93,000,000 49,000,000 120,000,000 27,000,000 94,000,000 27,000,000 87,000,000 58,000,000 51,000,000 86,000,000 58,000,000 76,000,000 52,000,000 92,000,000 52,000,000 64,000,000 62,000,000 65,000,000 63,000,000 112,000,000 18,000,000 64,000,000 32,000,000 57,000,000 75,000,000 66,000,000 74,000,000 76,000,000 54,000,000 20,000,000 30,000,000 28,000,000 19,000,000 37,000,000          
          income taxes paid, net of refunds
        120,000,000  189,000,000 459,000,000 233,000,000 203,000,000 297,000,000 309,000,000 244,000,000 152,000,000 255,000,000 206,000,000 128,000,000 143,000,000 154,000,000 121,000,000 82,000,000 91,000,000 165,000,000 74,000,000 129,000,000 224,000,000 49,000,000 53,000,000 74,000,000 82,000,000 164,000,000 33,000,000 63,000,000 67,000,000 149,000,000 58,000,000 746,000,000 50,000,000 58,000,000 65,000,000 64,000,000 48,000,000 41,000,000 69,000,000 62,000,000 72,000,000 46,000,000 76,000,000 138,000,000 66,000,000 148,000,000 59,000,000 40,000,000 60,000,000 -22,000,000 36,000,000 90,000,000 53,000,000 10,000,000 53,000,000 59,000,000 53,000,000          
          net sales (purchases) of short-term investments - non fiduciary
                -5,046,000,000   280,000,000 -190,000,000   -164,000,000                                                    
          issuance of debt
             1,984,000,000 5,942,000,000 744,000,000 496,000,000 -1,657,000,000 3,128,000,000 2,800,000,000 2,060,000,000 863,000,000 250,000,000 2,093,000,000 2,060,000,000 1,134,000,000 1,359,000,000 2,688,000,000 871,000,000 1,794,000,000 1,408,000,000 1,744,000,000 808,000,000 659,000,000 992,000,000 738,000,000 673,000,000 1,011,000,000 1,045,000,000 1,857,000,000 1,049,000,000 1,575,000,000 870,000,000 931,000,000 2,129,000,000 1,195,000,000 1,150,000,000 257,000,000 75,000,000 103,000,000 1,040,000,000 429,000,000                
          cash, cash equivalents and funds held on behalf of clients at beginning of year
                                                                           
          cash, cash equivalents and funds held on behalf of clients at end of year
                                                                           
          net purchases of short-term investments - non fiduciary
            -145,000,000                                                               
          net purchases (sales) of short-term investments - non fiduciary
                                                                           
          net sales of short-term investments - non fiduciary
             -31,000,000 -7,000,000   19,000,000                                                          
          redeemable and non-redeemable noncontrolling interests, and other financing activities
             -50,000,000 -48,000,000                                                             
          noncontrolling interests and other financing activities
                -6,000,000 -15,000,000 -35,000,000 -6,000,000 -21,000,000 -13,000,000 -24,000,000 -13,000,000 -8,000,000 -33,000,000 -16,000,000 -68,000,000 -4,000,000 -45,000,000 -26,000,000 40,000,000 -22,000,000 -20,000,000 -38,000,000 -23,000,000 -14,000,000 -6,000,000   -11,000,000 -8,000,000 -2,000,000 -6,000,000 -9,000,000 -20,000,000 -42,000,000                             
          cash and cash equivalents classified as held for sale
                 -3,000,000                                                          
          payments for investments
                    -12,000,000 -56,000,000 -30,000,000 -9,000,000 -23,000,000 -39,000,000 -11,000,000 -18,000,000 -17,000,000 -20,000,000 -17,000,000 -43,000,000 -19,000,000 -34,000,000 -46,000,000 -14,000,000 -15,000,000 -29,000,000 -25,000,000 -11,000,000 -23,000,000                                   
          cash and cash equivalents and funds held on behalf of clients at beginning of year
                                                                           
          cash and cash equivalents and funds held on behalf of clients at end of year
                                                                           
          issuance of shares for employee benefit plans
                     10,000,000 -50,000,000 -116,000,000 -8,000,000 18,000,000 -53,000,000 -87,000,000 -8,000,000 16,000,000 -45,000,000 -112,000,000 2,000,000 11,000,000 -46,000,000 -98,000,000 -10,000,000 11,000,000 -41,000,000 -109,000,000 21,000,000 -54,000,000 -85,000,000 -59,000,000 17,000,000 -22,000,000 -65,000,000 -102,000,000 20,000,000 4,000,000 48,000,000 18,000,000 14,000,000 26,000,000 36,000,000                     
          gain from sales of businesses and investments
                                           2,000,000 -6,000,000 -35,000,000 -52,000,000 -9,000,000 -1,000,000 -19,000,000 -33,000,000 -3,000,000 -5,000,000                      
          fiduciary receivables
                         1,979,000,000 -1,454,000,000 -166,000,000 -89,000,000 589,000,000 -832,000,000 -808,000,000 -583,000,000 1,100,000,000 -317,000,000 -609,000,000 -1,445,000,000 1,649,000,000 -278,000,000 -605,000,000 976,000,000 -327,000,000 337,000,000 -944,000,000 1,442,000,000 -303,000,000 399,000,000 -196,000,000 911,000,000 -289,000,000 173,000,000 1,551,000,000 -728,000,000 165,000,000 -42,000,000                     
          short-term investments — funds held on behalf of clients
                         -400,000,000 -358,000,000 -28,000,000 390,000,000 -84,000,000 -385,000,000 -237,000,000 39,000,000 -324,000,000 -420,000,000 -541,000,000 411,000,000 -577,000,000 41,000,000 -195,000,000 -415,000,000 44,000,000 -330,000,000 -160,000,000 11,000,000 -164,000,000 -285,000,000 150,000,000 148,000,000 -11,000,000 63,000,000                         
          fiduciary liabilities
                         -1,579,000,000 1,812,000,000 194,000,000 -301,000,000 -505,000,000 1,217,000,000 1,045,000,000 544,000,000 -776,000,000 737,000,000 1,150,000,000 1,034,000,000 -1,072,000,000 237,000,000 800,000,000 -560,000,000 282,000,000 -7,000,000 1,104,000,000 -1,453,000,000 467,000,000 -114,000,000 46,000,000 -1,059,000,000 300,000,000 -236,000,000 -1,549,000,000 632,000,000 106,000,000 364,000,000 1,314,000,000 706,000,000                   
          net sales (purchases) of short-term investments — non-fiduciary
                         -24,000,000 -116,000,000 138,000,000   -484,000,000 -38,000,000 42,000,000 55,000,000   -8,000,000 4,000,000                                      
          acquisition of businesses, net of cash acquired
                            -34,000,000 -334,000,000 -24,000,000 -15,000,000 -8,000,000 -21,000,000 -29,000,000 -23,000,000 -103,000,000 -46,000,000 -681,000,000 -15,000,000 -167,000,000 -16,000,000 10,000,000 -3,000,000 -2,000,000 -21,000,000 -381,000,000 -78,000,000 -5,000,000 -2,000,000                     
          sale of businesses, net of cash sold
                         -1,000,000   30,000,000 9,000,000 36,000,000 1,000,000 6,000,000 -2,000,000 -9,000,000 2,000,000 -1,000,000 1,000,000 4,195,000,000 -2,000,000                                 
          effect of exchange rates on cash and cash equivalents
                         -41,000,000 27,000,000 -16,000,000 109,000,000 25,000,000 26,000,000 -82,000,000 39,000,000 -36,000,000 -19,000,000 37,000,000 -42,000,000 -13,000,000                                      
          net increase in cash and cash equivalents
                         -482,000,000   63,000,000        172,000,000 -3,000,000 -110,000,000 -159,000,000 65,000,000 233,000,000 20,000,000 -52,000,000 45,000,000 -27,000,000 81,000,000 -14,000,000   4,000,000   -139,000,000 117,000,000 -37,000,000 51,000,000   336,000,000 75,000,000 -162,000,000 205,000,000             
          cash and cash equivalents at beginning of period
                         884,000,000  790,000,000 656,000,000 756,000,000 431,000,000  384,000,000  374,000,000 477,000,000 291,000,000 272,000,000 346,000,000 217,000,000 582,000,000          
          cash and cash equivalents at end of period
                         -482,000,000 269,000,000 822,000,000  64,000,000 67,000,000 690,000,000 188,000,000 21,000,000 -19,000,000 600,000,000 172,000,000 -3,000,000 -110,000,000 597,000,000 65,000,000 233,000,000 451,000,000  45,000,000 -27,000,000 465,000,000  31,000,000 -11,000,000 378,000,000 -36,000,000 80,000,000 338,000,000 408,000,000 -37,000,000 323,000,000 -5,000,000 -382,000,000 682,000,000 75,000,000 -162,000,000 422,000,000 43,000,000 36,000,000 501,000,000          
          (gain) from sales of businesses
                                                                           
          net (decrease) in cash and cash equivalents
                           -62,000,000                                                
          less: income from discontinued operations, net of income taxes
                                       6,000,000 -4,000,000 821,000,000 40,000,000                                 
          loss from sales of businesses and investments
                                        -1,000,000 1,000,000 2,000,000                                 
          restructuring reserves
                            -15,000,000 -30,000,000 -22,000,000 -60,000,000 65,000,000 -44,000,000 7,000,000 -25,000,000 9,000,000 2,000,000 36,000,000 -24,000,000 -8,000,000 79,000,000 99,000,000     -6,000,000 -6,000,000 -6,000,000 -13,000,000 -13,000,000 -22,000,000 -40,000,000 -16,000,000                     
          cash and cash equivalents at beginning of year
                                                                           
          cash and cash equivalents at end of year
                                                                           
          less: net income from discontinued operations
                               -1,000,000      -2,000,000                                      
          loss from sales of businesses
                             -25,000,000  -1,000,000 -3,000,000 -4,000,000  3,000,000 1,000,000                                    
          net purchases of short-term investments — non-fiduciary
                                                                           
          net decrease in cash and cash equivalents
                              67,000,000 -100,000,000  21,000,000 -19,000,000 -56,000,000                                        
          cash from operating activities - continuing operations
                                    711,000,000 562,000,000 273,000,000 140,000,000 -147,000,000 254,000,000 182,000,000                                 
          cash from operating activities - discontinued operations
                                        6,000,000 58,000,000                                 
          cash from investing activities - continuing operations
                                    -53,000,000 -95,000,000 -167,000,000 346,000,000 1,033,000,000 1,480,000,000 28,000,000                                 
          cash from investing activities - discontinued operations
                                        -4,000,000 -15,000,000                                 
          cash from financing activities - continuing operations
                                    -444,000,000 -457,000,000 -135,000,000 -663,000,000 -878,000,000 -1,512,000,000 -258,000,000                                 
          cash from financing activities - discontinued operations
                                                                           
          net sales of short-term investments — non-fiduciary
                                   41,000,000               42,000,000                         
          pension, other postretirement and other postemployment liabilities
                                       -53,000,000 -41,000,000 -60,000,000 -41,000,000                                 
          net sale of short-term investments — non-fiduciary
                                       415,000,000                                    
          effect of exchange rate changes on cash and cash equivalents
                                       18,000,000 57,000,000 9,000,000 25,000,000 -49,000,000 -8,000,000 7,000,000 11,000,000 -17,000,000 -112,000,000 -4,000,000 -39,000,000 -16,000,000 27,000,000 -24,000,000 5,000,000 8,000,000 10,000,000    -16,000,000               
          net sale (purchases) of short-term investments — non-fiduciary
                                        1,107,000,000 -2,545,000,000 94,000,000                                 
          amortization of intangible assets
                                          43,000,000 70,000,000 72,000,000 68,000,000 67,000,000 77,000,000 78,000,000 79,000,000 80,000,000 90,000,000 87,000,000 86,000,000 99,000,000 104,000,000 104,000,000 91,000,000 91,000,000 91,000,000 30,000,000   24,000,000 22,000,000 23,000,000 15,000,000 11,000,000 14,000,000 12,000,000 9,000,000 10,000,000 13,000,000 12,000,000 11,000,000 
          pension, other post-retirement and other post-employment liabilities
                                           112,000,000 -42,000,000 22,000,000 -50,000,000 -39,000,000 -69,000,000 -56,000,000 -66,000,000 -73,000,000 -98,000,000 -128,000,000 -196,000,000                     
          proceeds from sale of businesses
                                           3,000,000 1,000,000 6,000,000 97,000,000 151,000,000 2,000,000 11,000,000 41,000,000 47,000,000 1,000,000 1,000,000        1,000,000 10,000,000 128,000,000          
          net (purchases) sales of short-term investments — non-fiduciary
                                             333,000,000 -227,000,000  88,000,000                           
          proceeds from sale of long-term investments
                                                13,000,000 7,000,000 3,000,000 3,000,000 6,000,000 42,000,000                      
          purchases of long-term investments
                                                -2,000,000 -1,000,000 -5,000,000 -4,000,000 -10,000,000 -3,000,000                     
          (purchases) sales of shares (from) to noncontrolling interests
                                                -5,000,000                         
          dividends paid to noncontrolling interests
                                                -3,000,000 -17,000,000 -1,000,000 -8,000,000                        
          proceeds from sale-leaseback
                                                                           
          deposit with trustee
                                                                           
          short term investments - funds held on behalf of clients
                                                   -2,000,000 96,000,000 -271,000,000 -322,000,000                     
          net sales (purchases) of short-term investments - non-fiduciary
                                                     183,000,000         97,000,000             
          sales (purchases) of shares to (from) noncontrolling interests
                                                                           
          net sales of short-term investments - non-fiduciary
                                                       -24,000,000 283,000,000   218,000,000                
          purchase of shares from noncontrolling interests
                                                    1,000,000 -1,000,000                     
          cash from operations
                                                      54,000,000                     
          sales of long-term investments
                                                      18,000,000 15,000,000 36,000,000  79,000,000 17,000,000 5,000,000 11,000,000 66,000,000 5,000,000 9,000,000 7,000,000          
          net (purchases) sales of short-term investments - non-fiduciary
                                                      -16,000,000                     
          adjustments to reconcile net income to cash provided by operating activities:
                                                                           
          pension and other post employment liabilities
                                                                           
          adjustments to reconcile net income to cash (used for) provided by operating activities:
                                                                           
          stock compensation expense
                                                        55,000,000 58,000,000 47,000,000 74,000,000 43,000,000   57,000,000 55,000,000 40,000,000 52,000,000 60,000,000 82,000,000 45,000,000 56,000,000 51,000,000    
          short-term investments - funds held on behalf of clients
                                                                           
          purchase of long-term investments
                                                                           
          purchase of treasury stock
                                                                           
          issuance of stock for employee benefit plans
                                                        49,000,000 3,000,000 77,000,000 85,000,000 17,000,000 46,000,000 35,000,000             
          cash dividends to stockholders
                                                                           
          change in funds held on behalf of clients
                                                         -116,000,000 315,000,000 427,000,000 -167,000,000 237,000,000 396,000,000             
          sales of long term investments
                                                                           
          purchases of long term investments
                                                                           
          net sales (purchases) of short term investments - non-fiduciary
                                                                           
          net purchases of short term investments - funds held on behalf of clients
                                                                           
          net purchases of short-term investments - funds held on behalf of clients
                                                                           
          see accompanying notes to the condensed consolidated financial statements (unaudited).
                                                                           
          cash flows from operating activities:
                                                                           
          losses from sale of businesses
                                                            7,000,000               
          cash flows from investing activities:
                                                                           
          cash flows from financing activities:
                                                                           
          repayments of debt
                                                                           
          gains from sale of businesses
                                                                           
          depreciation and amortization
                                                              58,000,000             
          stock-based compensation expense
                                                              66,000,000             
          issuance (repayments) of debt
                                                              73,000,000             
          effect of exchange rate changes on cash
                                                              47,000,000    -10,000,000 8,000,000 19,000,000 15,000,000 15,000,000 5,000,000    
          gain from disposal of operations
                                                                           
          depreciation and amortization of fixed assets
                                                               32,000,000 36,000,000 37,000,000          
          change in funds held on behalf of brokerage and consulting clients
                                                               -67,000,000 -399,000,000 512,000,000 -250,000,000 -200,000,000 500,000,000 -300,000,000 -110,000,000 560,000,000 -250,000,000   
          net receivables
                                                               80,000,000 -41,000,000 179,000,000          
          sales (purchases) of short-term investments
                                                               58,000,000            
          issuance of common stock
                                                               8,000,000 15,000,000 27,000,000 7,000,000 32,000,000 3,000,000 -4,000,000 8,000,000 11,000,000 -7,000,000 53,000,000 
          treasury stock transactions - net
                                                                 28,000,000          
          short-term repayments
                                                                           
          issuance of long-term debt
                                                                  1,000,000 15,000,000 348,000,000 17,000,000 410,000,000 250,000,000 378,000,000 3,000,000 
          repayments of long-term debt
                                                                           
          acquisition of subsidiaries, net of cash acquired
                                                                           
          short-term borrowings (repayments)
                                                                           
          purchases of short-term investments
                                                                           
          repayment of short-term borrowings
                                                                           
          cash flows - operating activities:
                                                                           
          adjustments to reconcile net income to cash provided by operating activities
                                                                           
          depreciation and amortization of property, equipment and software
                                                                  34,000,000 47,000,000 36,000,000 38,000,000 40,000,000 40,000,000 44,000,000 47,000,000 46,000,000 
          valuation changes on investments, income on disposals and net bond amortization
                                                                  3,000,000 1,000,000 5,000,000       
          income taxes
                                                                  -42,000,000   21,000,000 73,000,000 61,000,000    
          contribution to major defined benefit pension plans in excess of expense
                                                                           
          cash paid (in excess of) less than expense for restructuring plans
                                                                  15,000,000 13,000,000 19,000,000       
          provision for new york and other state settlements
                                                                         1,000,000 1,000,000 
          change in insurance underwriting assets and liabilities
                                                                           
          net reinsurance and net due & deferred premium
                                                                  -2,000,000         
          prepaid premiums
                                                                  1,000,000 1,000,000 5,000,000       
          deferred policy acquisition costs
                                                                       1,000,000    
          policy liabilities
                                                                   -5,000,000 8,000,000  2,000,000 43,000,000 209,000,000   
          net due reinsurance
                                                                           
          change in other assets and liabilities
                                                                           
          other assets and liabilities - net
                                                                           
          cash flows - investing activities:
                                                                           
          sale of investments
                                                                           
          fixed maturities
                                                                           
          maturities
                                                                  1,000,000 15,000,000 38,000,000 51,000,000 13,000,000 38,000,000 34,000,000 100,000,000 22,000,000 
          calls and prepayments
                                                                  4,000,000 25,000,000 13,000,000 28,000,000 20,000,000 61,000,000 42,000,000 66,000,000 
          sales
                                                                  -10,000,000 20,000,000 176,000,000 201,000,000 153,000,000 184,000,000 354,000,000 530,000,000 361,000,000 
          equity securities and other investments
                                                                  1,000,000       
          purchase of investments
                                                                           
          other investments
                                                                     20,000,000 12,000,000 11,000,000 128,000,000 6,000,000 12,000,000 
          short-term investments - net
                                                                     154,000,000 168,000,000 41,000,000    
          acquisition of subsidiaries
                                                                           
          net proceeds from sale of discontinued operations
                                                                           
          property and equipment and other - net
                                                                           
          cash flows - financing activities:
                                                                           
          repayments of short-term borrowings - net
                                                                           
          cash used by financing activities
                                                                           
          increase in cash
                                                                     -85,000,000      
          cash at beginning of period
                                                                  584,000,000 281,000,000 476,000,000 
          cash at end of period
                                                                  12,000,000 14,000,000 452,000,000 -85,000,000 55,000,000 351,000,000 36,000,000 -26,000,000 451,000,000 
          cash provided (used) by operating activities
                                                                           
          proceeds from sale of operations
                                                                   2,914,000,000 1,000,000   20,000,000 
          cash provided (used) by investing activities
                                                                           
          adjustments to reconcile net income to cash from operating activities
                                                                           
          net reinsurance and net due and deferred premium
                                                                    2,000,000       
          cash used by investing activities
                                                                           
          contribution to major defined benefit pension plans (in excess of) less than expense
                                                                           
          cash paid in excess of expense for restructuring plans
                                                                           
          changes in insurance underwriting assets and liabilities:
                                                                           
          operating receivables
                                                                     -10,000,000 23,000,000 36,000,000 -18,000,000   
          other assets including prepaid premiums
                                                                     3,000,000 14,000,000 25,000,000 35,000,000   
          other liabilities
                                                                       36,000,000    
          changes in other assets and liabilities:
                                                                           
          accrued compensation and general expenses
                                                                           
          other assets and liabilities- net
                                                                     168,000,000 -135,000,000 147,000,000    
          cash provided by operating activities
                                                                     75,000,000     697,000,000 
          equity securities
                                                                     26,000,000 4,000,000   
          cash provided by (used by) investing activities
                                                                           
          issuances (repayments) of short-term borrowings - net
                                                                           
          cash paid in excess of expense for 2005 restructuring plan
                                                                           
          repayment of short-term borrowings - net
                                                                           
          repayment of long-term debt
                                                                           
          contribution to major defined benefit pension plan in excess of expense
                                                                           
          general expenses
                                                                           
          increase (decrease) in cash
                                                                       70,000,000    
          amortization of stock awards
                                                                        33,000,000   
          pension expense in excess of cash paid to major defined benefit plans
                                                                        16,000,000   
          cash paid for 2005 restructuring plan in excess of expense
                                                                           
          preferred stock transaction
                                                                           
          issuance of short-term borrowings - net
                                                                        247,000,000   
          decrease in cash
                                                                           
          insurance operating assets and liabilities, net of reinsurance
                                                                          97,000,000 
          amortization of stock-based compensation plans
                                                                          41,000,000 
          2005 restructuring plan
                                                                           
          other receivables and liabilities - net
                                                                          341,000,000