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v3.21.1

Segment Information (Operations By Segment) (Detail) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Segment Reporting Information [Line Items] |  |
Net premiums written | $ 8,662 | $ 7,977
Net premiums earned | 8,221 | 7,794
Losses and loss expenses | 5,053 | 4,485
Policy benefits | 167 | 129
Policy acquisition costs | 1,665 | 1,615
Administrative expenses | 744 | 741
Underwriting income (loss) | 592 | 824
Net investment income (loss) | 863 | 861
Other (income) expense | (490) | 55
Amortization of purchased intangibles | 72 | 73
Segment Income (loss) | 1,873 | 1,557
Realized Investment Gains (Losses) | 887 | (958)
Interest expense | 122 | 132
Income tax expense | 338 | 215
Net income | 2,300 | 252
Segment Reconciling Items |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 0 | 0
Net premiums earned | 0 | 0
Losses and loss expenses | (1) | (2)
Policy benefits | 4 | (56)
Policy acquisition costs | 0 | 0
Administrative expenses | 0 | 0
Underwriting income (loss) | (3) | 58
Net investment income (loss) | (41) | (24)
Other (income) expense | (45) | 32
Amortization of purchased intangibles | 0 | 0
Segment Income (loss) | 1 | 2
Realized Investment Gains (Losses) | (1) | (2)
Interest expense | 0 | 0
Income tax expense | 0 | 0
Net income | 0 | 0
North America Commercial P&C Insurance [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 3,664 | 3,252
Net premiums earned | 3,674 | 3,376
Losses and loss expenses | 2,560 | 2,181
Policy benefits | 0 | 0
Policy acquisition costs | 514 | 492
Administrative expenses | 254 | 259
Underwriting income (loss) | 346 | 444
Net investment income (loss) | 540 | 525
Other (income) expense | 2 | 6
Amortization of purchased intangibles | 0 | 0
Segment Income (loss) | 884 | 963
North America Personal P&C Insurance [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 1,098 | 1,107
Net premiums earned | 1,184 | 1,200
Losses and loss expenses | 819 | 683
Policy benefits | 0 | 0
Policy acquisition costs | 247 | 245
Administrative expenses | 60 | 68
Underwriting income (loss) | 58 | 204
Net investment income (loss) | 65 | 66
Other (income) expense | 1 | 2
Amortization of purchased intangibles | 3 | 3
Segment Income (loss) | 119 | 265
North America Agricultural Insurance [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 183 | 157
Net premiums earned | 110 | 94
Losses and loss expenses | 85 | 65
Policy benefits | 0 | 0
Policy acquisition costs | 12 | 11
Administrative expenses | 3 | 4
Underwriting income (loss) | 10 | 14
Net investment income (loss) | 7 | 9
Other (income) expense | 0 | 0
Amortization of purchased intangibles | 7 | 7
Segment Income (loss) | 10 | 16
Overseas General Insurance [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 2,890 | 2,598
Net premiums earned | 2,478 | 2,307
Losses and loss expenses | 1,263 | 1,258
Policy benefits | 0 | 0
Policy acquisition costs | 668 | 642
Administrative expenses | 266 | 258
Underwriting income (loss) | 281 | 149
Net investment income (loss) | 141 | 145
Other (income) expense | 1 | 4
Amortization of purchased intangibles | 12 | 12
Segment Income (loss) | 409 | 278
Global Reinsurance [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 207 | 218
Net premiums earned | 180 | 186
Losses and loss expenses | 120 | 87
Policy benefits | 0 | 0
Policy acquisition costs | 45 | 45
Administrative expenses | 8 | 10
Underwriting income (loss) | 7 | 44
Net investment income (loss) | 70 | 69
Other (income) expense | 0 | 0
Amortization of purchased intangibles | 0 | 0
Segment Income (loss) | 77 | 113
Life Insurance [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 620 | 645
Net premiums earned | 595 | 631
Losses and loss expenses | 198 | 202
Policy benefits | 163 | 185
Policy acquisition costs | 179 | 180
Administrative expenses | 82 | 76
Underwriting income (loss) | (27) | (12)
Net investment income (loss) | 98 | 95
Other (income) expense | (34) | (12)
Amortization of purchased intangibles | 1 | 1
Segment Income (loss) | 104 | 94
Corporate Segment [Member] |  |
Segment Reporting Information [Line Items] |  |
Net premiums written | 0 | 0
Net premiums earned | 0 | 0
Losses and loss expenses | 9 | 11
Policy benefits | 0 | 0
Policy acquisition costs | 0 | 0
Administrative expenses | 71 | 66
Underwriting income (loss) | (80) | (77)
Net investment income (loss) | (17) | (24)
Other (income) expense | (415) | 23
Amortization of purchased intangibles | 49 | 50
Segment Income (loss) | 269 | (174)
Realized Investment Gains (Losses) | 888 | (956)
Interest expense | 122 | 132
Income tax expense | 338 | 215
Net income | $ 697 | $ (1,477)

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