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Business Segments (Income Statement Information) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Segment Reporting Information [Line Items] |  |  |
Net written premiums | $ 9,128 | $ 8,405 | $ 8,059
Operating revenues |  |  |
Net earned premiums | 8,667 | 8,175 | 7,649
Net investment income | 1,805 | 2,159 | 1,935
Non-insurance warranty revenue | 1,574 | 1,430 | 1,252
Other revenues | 32 | 24 | 26
Total operating revenues | 12,078 | 11,788 | 10,862
Claims, Benefits and Expenses |  |  |
Net incurred claims and benefits | 6,361 | 6,327 | 6,149
Policyholders’ dividends | 25 | 22 | 21
Amortization of deferred acquisition costs | 1,490 | 1,443 | 1,410
Non-insurance warranty expense | 1,471 | 1,328 | 1,159
Other insurance related expenses | 1,160 | 1,062 | 1,028
Other expenses | 291 | 242 | 220
Total claims, benefits and expenses | 10,798 | 10,424 | 9,987
Core income (loss) before income tax | 1,280 | 1,364 | 875
Income tax (expense) benefit on core income (loss) | (232) | (258) | (140)
Core income (loss) | 1,048 | 1,106 | 735
Net investment gains (losses) | (199) | 120 | (54)
Income tax (expense) benefit on net investment gains (losses) | 45 | (24) | 9
Net investment gains (losses), after tax | (154) | 96 | (45)
Net income (loss) | 894 | 1,202 | 690
Operating Segments | Specialty |  |  |
Segment Reporting Information [Line Items] |  |  |
Net written premiums | 3,306 | 3,225 | 3,040
Operating revenues |  |  |
Net earned premiums | 3,203 | 3,076 | 2,883
Net investment income | 431 | 497 | 449
Non-insurance warranty revenue | 1,574 | 1,430 | 1,252
Other revenues | 1 | 1 | 1
Total operating revenues | 5,209 | 5,004 | 4,585
Claims, Benefits and Expenses |  |  |
Net incurred claims and benefits | 1,839 | 1,787 | 1,792
Policyholders’ dividends | 6 | 3 | 3
Amortization of deferred acquisition costs | 656 | 643 | 621
Non-insurance warranty expense | 1,471 | 1,328 | 1,159
Other insurance related expenses | 336 | 296 | 280
Other expenses | 51 | 47 | 50
Total claims, benefits and expenses | 4,359 | 4,104 | 3,905
Core income (loss) before income tax | 850 | 900 | 680
Income tax (expense) benefit on core income (loss) | (182) | (196) | (145)
Core income (loss) | 668 | 704 | 535
Operating Segments | Commercial |  |  |
Segment Reporting Information [Line Items] |  |  |
Net written premiums | 4,193 | 3,595 | 3,565
Operating revenues |  |  |
Net earned premiums | 3,923 | 3,552 | 3,323
Net investment income | 488 | 624 | 513
Non-insurance warranty revenue | 0 | 0 | 0
Other revenues | 30 | 23 | 25
Total operating revenues | 4,441 | 4,199 | 3,861
Claims, Benefits and Expenses |  |  |
Net incurred claims and benefits | 2,607 | 2,540 | 2,375
Policyholders’ dividends | 19 | 19 | 18
Amortization of deferred acquisition costs | 634 | 594 | 592
Non-insurance warranty expense | 0 | 0 | 0
Other insurance related expenses | 557 | 511 | 506
Other expenses | 36 | 38 | 34
Total claims, benefits and expenses | 3,853 | 3,702 | 3,525
Core income (loss) before income tax | 588 | 497 | 336
Income tax (expense) benefit on core income (loss) | (122) | (103) | (69)
Core income (loss) | 466 | 394 | 267
Operating Segments | International |  |  |
Segment Reporting Information [Line Items] |  |  |
Net written premiums | 1,164 | 1,101 | 961
Operating revenues |  |  |
Net earned premiums | 1,070 | 1,057 | 940
Net investment income | 63 | 57 | 58
Non-insurance warranty revenue | 0 | 0 | 0
Other revenues | 1 | 0 | 0
Total operating revenues | 1,134 | 1,114 | 998
Claims, Benefits and Expenses |  |  |
Net incurred claims and benefits | 637 | 652 | 629
Policyholders’ dividends | 0 | 0 | 0
Amortization of deferred acquisition costs | 200 | 206 | 197
Non-insurance warranty expense | 0 | 0 | 0
Other insurance related expenses | 146 | 144 | 136
Other expenses | 26 | (2) | (7)
Total claims, benefits and expenses | 1,009 | 1,000 | 955
Core income (loss) before income tax | 125 | 114 | 43
Income tax (expense) benefit on core income (loss) | (19) | (28) | (5)
Core income (loss) | 106 | 86 | 38
Operating Segments | Life & Group |  |  |
Segment Reporting Information [Line Items] |  |  |
Net written premiums | 467 | 485 | 494
Operating revenues |  |  |
Net earned premiums | 473 | 491 | 504
Net investment income | 804 | 966 | 851
Non-insurance warranty revenue | 0 | 0 | 0
Other revenues | (1) | 0 | 0
Total operating revenues | 1,276 | 1,457 | 1,355
Claims, Benefits and Expenses |  |  |
Net incurred claims and benefits | 1,202 | 1,239 | 1,286
Policyholders’ dividends | 0 | 0 | 0
Amortization of deferred acquisition costs | 0 | 0 | 0
Non-insurance warranty expense | 0 | 0 | 0
Other insurance related expenses | 118 | 103 | 109
Other expenses | 9 | 10 | 7
Total claims, benefits and expenses | 1,329 | 1,352 | 1,402
Core income (loss) before income tax | (53) | 105 | (47)
Income tax (expense) benefit on core income (loss) | 44 | 21 | 56
Core income (loss) | (9) | 126 | 9
Operating Segments | Corporate & Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Net written premiums | (1) | 0 | 0
Operating revenues |  |  |
Net earned premiums | (1) | 0 | 0
Net investment income | 19 | 15 | 64
Non-insurance warranty revenue | 0 | 0 | 0
Other revenues | 6 | 6 | 5
Total operating revenues | 24 | 21 | 69
Claims, Benefits and Expenses |  |  |
Net incurred claims and benefits | 76 | 109 | 67
Policyholders’ dividends | 0 | 0 | 0
Amortization of deferred acquisition costs | 0 | 0 | 0
Non-insurance warranty expense | 0 | 0 | 0
Other insurance related expenses | 4 | 9 | (2)
Other expenses | 174 | 155 | 141
Total claims, benefits and expenses | 254 | 273 | 206
Core income (loss) before income tax | (230) | (252) | (137)
Income tax (expense) benefit on core income (loss) | 47 | 48 | 23
Core income (loss) | (183) | (204) | (114)
Eliminations |  |  |
Segment Reporting Information [Line Items] |  |  |
Net written premiums | (1) | (1) | (1)
Operating revenues |  |  |
Net earned premiums | (1) | (1) | (1)
Net investment income | 0 | 0 | 0
Non-insurance warranty revenue | 0 | 0 | 0
Other revenues | (5) | (6) | (5)
Total operating revenues | (6) | (7) | (6)
Claims, Benefits and Expenses |  |  |
Net incurred claims and benefits | 0 | 0 | 0
Policyholders’ dividends | 0 | 0 | 0
Amortization of deferred acquisition costs | 0 | 0 | 0
Non-insurance warranty expense | 0 | 0 | 0
Other insurance related expenses | (1) | (1) | (1)
Other expenses | (5) | (6) | (5)
Total claims, benefits and expenses | (6) | (7) | (6)
Core income (loss) before income tax | 0 | 0 | 0
Income tax (expense) benefit on core income (loss) | 0 | 0 | 0
Core income (loss) | $ 0 | $ 0 | $ 0

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