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v3.21.2

Segment Information (Operations By Segment) (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | $ 9,546 |  | $ 8,355 | $ 18,208 | $ 16,332
Net premiums earned | 8,813 |  | 8,128 | 17,034 | 15,922
Losses and loss expenses | 5,006 |  | 6,577 | 10,059 | 11,062
Policy benefits | 185 |  | 223 | 352 | 352
Policy acquisition costs | 1,698 |  | 1,593 | 3,363 | 3,208
Administrative expenses | 775 |  | 727 | 1,519 | 1,468
Underwriting income (loss) | 1,149 |  | (992) | 1,741 | (168)
Net investment income (loss) | 884 |  | 827 | 1,747 | 1,688
Other (income) expense | (777) | [1] | 58 | (1,267) | 113
Amortization of purchased intangibles | 73 |  | 72 | 145 | 145
Segment Income (loss) | 2,737 |  | (295) | 4,610 | 1,262
Realized Investment Gains (Losses) | (33) |  | 30 | 854 | (928)
Interest expense | 122 |  | 128 | 244 | 260
Income tax expense | 317 |  | (62) | 655 | 153
Net income (loss) | 2,265 |  | (331) | 4,565 | (79)
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 | 3 |  | (1) | 2 | (3)
Policy benefits | 15 |  | 40 | 19 | (16)
Policy acquisition costs | 0 |  | 0 | 0 | 0
Administrative expenses | 0 |  | 0 | 0 | 0
Underwriting income (loss) | (18) |  | (39) | (21) | 19
Net investment income (loss) | (39) |  | (8) | (80) | (32)
Other (income) expense | (54) | [1] | (48) | (99) | (16)
Amortization of purchased intangibles | 0 |  | 0 | 0 | 0
Segment Income (loss) | (3) |  | 1 | (2) | 3
Realized Investment Gains (Losses) | 3 |  | (1) | 2 | (3)
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 | 4,285 |  | 3,720 | 7,949 | 6,972
Net premiums earned | 3,803 |  | 3,595 | 7,477 | 6,971
Losses and loss expenses | 2,426 |  | 3,498 | 4,986 | 5,679
Policy benefits | 0 |  | 0 | 0 | 0
Policy acquisition costs | 489 |  | 471 | 1,003 | 963
Administrative expenses | 245 |  | 249 | 499 | 508
Underwriting income (loss) | 643 |  | (623) | 989 | (179)
Net investment income (loss) | 535 |  | 509 | 1,075 | 1,034
Other (income) expense | 14 | [1] | 6 | 16 | 12
Amortization of purchased intangibles | 0 |  | 0 | 0 | 0
Segment Income (loss) | 1,164 |  | (120) | 2,048 | 843
North America Personal P&C Insurance [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 1,363 |  | 1,327 | 2,461 | 2,434
Net premiums earned | 1,224 |  | 1,192 | 2,408 | 2,392
Losses and loss expenses | 676 |  | 762 | 1,495 | 1,445
Policy benefits | 0 |  | 0 | 0 | 0
Policy acquisition costs | 245 |  | 231 | 492 | 476
Administrative expenses | 67 |  | 66 | 127 | 134
Underwriting income (loss) | 236 |  | 133 | 294 | 337
Net investment income (loss) | 64 |  | 65 | 129 | 131
Other (income) expense | (5) | [1] | 1 | (4) | 3
Amortization of purchased intangibles | 3 |  | 3 | 6 | 6
Segment Income (loss) | 302 |  | 194 | 421 | 459
North America Agricultural Insurance [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 512 |  | 461 | 695 | 618
Net premiums earned | 410 |  | 376 | 520 | 470
Losses and loss expenses | 331 |  | 313 | 416 | 378
Policy benefits | 0 |  | 0 | 0 | 0
Policy acquisition costs | 27 |  | 29 | 39 | 40
Administrative expenses | 3 |  | 3 | 6 | 7
Underwriting income (loss) | 49 |  | 31 | 59 | 45
Net investment income (loss) | 8 |  | 7 | 15 | 16
Other (income) expense | 0 | [1] | 1 | 0 | 1
Amortization of purchased intangibles | 6 |  | 6 | 13 | 13
Segment Income (loss) | 51 |  | 31 | 61 | 47
Overseas General Insurance [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 2,497 |  | 2,021 | 5,387 | 4,619
Net premiums earned | 2,579 |  | 2,194 | 5,057 | 4,501
Losses and loss expenses | 1,186 |  | 1,485 | 2,449 | 2,743
Policy benefits | 0 |  | 0 | 0 | 0
Policy acquisition costs | 699 |  | 624 | 1,367 | 1,266
Administrative expenses | 279 |  | 241 | 545 | 499
Underwriting income (loss) | 415 |  | (156) | 696 | (7)
Net investment income (loss) | 149 |  | 121 | 290 | 266
Other (income) expense | 2 | [1] | 5 | 3 | 9
Amortization of purchased intangibles | 13 |  | 11 | 25 | 23
Segment Income (loss) | 549 |  | (51) | 958 | 227
Global Reinsurance [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 274 |  | 207 | 481 | 425
Net premiums earned | 192 |  | 163 | 372 | 349
Losses and loss expenses | 110 |  | 73 | 230 | 160
Policy benefits | 0 |  | 0 | 0 | 0
Policy acquisition costs | 47 |  | 42 | 92 | 87
Administrative expenses | 10 |  | 9 | 18 | 19
Underwriting income (loss) | 25 |  | 39 | 32 | 83
Net investment income (loss) | 81 |  | 60 | 151 | 129
Other (income) expense | 0 | [1] | 1 | 0 | 1
Amortization of purchased intangibles | 0 |  | 0 | 0 | 0
Segment Income (loss) | 106 |  | 98 | 183 | 211
Life Insurance [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net premiums written | 615 |  | 619 | 1,235 | 1,264
Net premiums earned | 605 |  | 608 | 1,200 | 1,239
Losses and loss expenses | 185 |  | 171 | 383 | 373
Policy benefits | 170 |  | 183 | 333 | 368
Policy acquisition costs | 191 |  | 196 | 370 | 376
Administrative expenses | 83 |  | 82 | 165 | 158
Underwriting income (loss) | (24) |  | (24) | (51) | (36)
Net investment income (loss) | 101 |  | 95 | 199 | 190
Other (income) expense | (26) | [1] | (17) | (60) | (29)
Amortization of purchased intangibles | 1 |  | 1 | 2 | 2
Segment Income (loss) | 102 |  | 87 | 206 | 181
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 | 89 |  | 276 | 98 | 287
Policy benefits | 0 |  | 0 | 0 | 0
Policy acquisition costs | 0 |  | 0 | 0 | 0
Administrative expenses | 88 |  | 77 | 159 | 143
Underwriting income (loss) | (177) |  | (353) | (257) | (430)
Net investment income (loss) | (15) |  | (22) | (32) | (46)
Other (income) expense | (708) | [1] | 109 | (1,123) | 132
Amortization of purchased intangibles | 50 |  | 51 | 99 | 101
Segment Income (loss) | 466 |  | (535) | 735 | (709)
Realized Investment Gains (Losses) | (36) |  | 31 | 852 | (925)
Interest expense | 122 |  | 128 | 244 | 260
Income tax expense | 317 |  | (62) | 655 | 153
Net income (loss) | $ (9) |  | $ (570) | $ 688 | $ (2,047)
[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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