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v3.21.2

Segment Information (Operations By Segment) (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | $ 10,510 |  | $ 9,078 | $ 28,718 | $ 25,410
Net premiums earned | 10,000 |  | 8,765 | 27,034 | 24,687
Losses and loss expenses | 6,629 |  | 5,835 | 16,688 | 16,897
Policy benefits | 151 |  | 198 | 503 | 550
Policy acquisition costs | 1,778 |  | 1,645 | 5,141 | 4,853
Administrative expenses | 806 |  | 733 | 2,325 | 2,201
Underwriting income (loss) | 636 |  | 354 | 2,377 | 186
Net investment income (loss) | 866 |  | 840 | 2,613 | 2,528
Other (income) expense | (763) |  | (485) | (2,030) | (372)
Amortization of purchased intangibles | 71 |  | 72 | 216 | 217
Segment Income (loss) | 2,194 |  | 1,607 | 6,804 | 2,869
Realized Investment Gains (Losses) | (21) |  | (141) | 833 | (1,069)
Interest expense | 122 |  | 130 | 366 | 390
Income tax expense | 218 |  | 142 | 873 | 295
Net income (loss) | 1,833 |  | 1,194 | 6,398 | 1,115
Segment Reconciling Items |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 0 |  | 0 | 0 | 0
Net premiums earned | 0 |  | 0 | 0 | 0
Losses and loss expenses | (10) |  | 1 | (8) | (2)
Policy benefits | (24) |  | 24 | (5) | 8
Policy acquisition costs | 0 |  | 0 | 0 | 0
Administrative expenses | 0 |  | 0 | 0 | 0
Underwriting income (loss) | 34 |  | (25) | 13 | (6)
Net investment income (loss) | (55) |  | (32) | (135) | (64)
Other (income) expense | (31) | [1] | (56) | (130) | (72)
Amortization of purchased intangibles | 0 |  | 0 | 0 | 0
Segment Income (loss) | 10 |  | (1) | 8 | 2
Realized Investment Gains (Losses) | (10) |  | 1 | (8) | (2)
Interest expense | 0 |  | 0 | 0 | 0
Income tax expense | 0 |  | 0 | 0 | 0
Net income (loss) | 0 |  | 0 | 0 | 0
North America Commercial P&C Insurance [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 4,369 |  | 3,778 | 12,318 | 10,750
Net premiums earned | 3,954 |  | 3,456 | 11,431 | 10,427
Losses and loss expenses | 2,754 |  | 2,444 | 7,740 | 8,123
Policy benefits | 0 |  | 0 | 0 | 0
Policy acquisition costs | 537 |  | 489 | 1,540 | 1,452
Administrative expenses | 273 |  | 243 | 772 | 751
Underwriting income (loss) | 390 |  | 280 | 1,379 | 101
Net investment income (loss) | 507 |  | 510 | 1,582 | 1,544
Other (income) expense | 8 | [1] | 7 | 24 | 19
Amortization of purchased intangibles | 0 |  | 0 | 0 | 0
Segment Income (loss) | 889 |  | 783 | 2,937 | 1,626
North America Personal P&C Insurance [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 1,300 |  | 1,285 | 3,761 | 3,719
Net premiums earned | 1,244 |  | 1,231 | 3,652 | 3,623
Losses and loss expenses | 846 |  | 961 | 2,341 | 2,406
Policy benefits | 0 |  | 0 | 0 | 0
Policy acquisition costs | 254 |  | 248 | 746 | 724
Administrative expenses | 73 |  | 65 | 200 | 199
Underwriting income (loss) | 71 |  | (43) | 365 | 294
Net investment income (loss) | 60 |  | 64 | 189 | 195
Other (income) expense | 1 | [1] | 1 | (3) | 4
Amortization of purchased intangibles | 2 |  | 2 | 8 | 8
Segment Income (loss) | 128 |  | 18 | 549 | 477
North America Agricultural Insurance [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 1,415 |  | 986 | 2,110 | 1,604
Net premiums earned | 1,338 |  | 971 | 1,858 | 1,441
Losses and loss expenses | 1,138 |  | 845 | 1,554 | 1,223
Policy benefits | 0 |  | 0 | 0 | 0
Policy acquisition costs | 61 |  | 56 | 100 | 96
Administrative expenses | 4 |  | 5 | 10 | 12
Underwriting income (loss) | 135 |  | 65 | 194 | 110
Net investment income (loss) | 6 |  | 7 | 21 | 23
Other (income) expense | 0 | [1] | 0 | 0 | 1
Amortization of purchased intangibles | 7 |  | 7 | 20 | 20
Segment Income (loss) | 134 |  | 65 | 195 | 112
Overseas General Insurance [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 2,596 |  | 2,238 | 7,983 | 6,857
Net premiums earned | 2,664 |  | 2,337 | 7,721 | 6,838
Losses and loss expenses | 1,487 |  | 1,192 | 3,936 | 3,935
Policy benefits | 0 |  | 0 | 0 | 0
Policy acquisition costs | 703 |  | 637 | 2,070 | 1,903
Administrative expenses | 266 |  | 260 | 811 | 759
Underwriting income (loss) | 208 |  | 248 | 904 | 241
Net investment income (loss) | 157 |  | 130 | 447 | 396
Other (income) expense | 0 | [1] | 1 | 3 | 10
Amortization of purchased intangibles | 11 |  | 10 | 36 | 33
Segment Income (loss) | 354 |  | 367 | 1,312 | 594
Global Reinsurance [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 221 |  | 181 | 702 | 606
Net premiums earned | 211 |  | 171 | 583 | 520
Losses and loss expenses | 192 |  | 154 | 422 | 314
Policy benefits | 0 |  | 0 | 0 | 0
Policy acquisition costs | 55 |  | 40 | 147 | 127
Administrative expenses | 9 |  | 9 | 27 | 28
Underwriting income (loss) | (45) |  | (32) | (13) | 51
Net investment income (loss) | 99 |  | 85 | 250 | 214
Other (income) expense | 0 | [1] | 0 | 0 | 1
Amortization of purchased intangibles | 0 |  | 0 | 0 | 0
Segment Income (loss) | 54 |  | 53 | 237 | 264
Life Insurance [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 609 |  | 610 | 1,844 | 1,874
Net premiums earned | 589 |  | 599 | 1,789 | 1,838
Losses and loss expenses | 179 |  | 183 | 562 | 556
Policy benefits | 175 |  | 174 | 508 | 542
Policy acquisition costs | 168 |  | 175 | 538 | 551
Administrative expenses | 82 |  | 80 | 247 | 238
Underwriting income (loss) | (15) |  | (13) | (66) | (49)
Net investment income (loss) | 102 |  | 95 | 301 | 285
Other (income) expense | (19) | [1] | (23) | (79) | (52)
Amortization of purchased intangibles | 2 |  | 1 | 4 | 3
Segment Income (loss) | 104 |  | 104 | 310 | 285
Corporate Segment [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 0 |  | 0 | 0 | 0
Net premiums earned | 0 |  | 0 | 0 | 0
Losses and loss expenses | 43 |  | 55 | 141 | 342
Policy benefits | 0 |  | 0 | 0 | 0
Policy acquisition costs | 0 |  | 0 | 0 | 0
Administrative expenses | 99 |  | 71 | 258 | 214
Underwriting income (loss) | (142) |  | (126) | (399) | (556)
Net investment income (loss) | (10) |  | (19) | (42) | (65)
Other (income) expense | (722) | [1] | (415) | (1,845) | (283)
Amortization of purchased intangibles | 49 |  | 52 | 148 | 153
Segment Income (loss) | 521 |  | 218 | 1,256 | (491)
Realized Investment Gains (Losses) | (11) |  | (142) | 841 | (1,067)
Interest expense | 122 |  | 130 | 366 | 390
Income tax expense | 218 |  | 142 | 873 | 295
Net income (loss) | $ 170 |  | $ (196) | $ 858 | $ (2,243)
[1] | Principally includes our share of operating income and market-to-market gains on private equities where we hold more than three percent. Refer to Note 11 for additional information.

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