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Supplementary Insurance Information - Table (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items] |  |  |
Deferred policy acquisition costs | $ 546 | $ 1,037 | $ 1,682
Reserves for future policy benefits, claims and unpaid losses and LAE | 53,572 | 51,250 | 46,992
Unearned premiums | 2,803 | 2,830 | 2,595
Net earned premiums | 5,118 | 5,207 | 4,889
Net investment income | 2,132 | 2,303 | 2,094
Benefits, claims, losses and settlement expenses | 4,503 | 4,458 | 4,041
Amortization of deferred policy acquisition costs | 866 | 923 | 860
Other operating expenses | 1,692 | 1,748 | 1,610
Net written premiums (excluding life) | 5,017 | 5,345 | 5,026
Property and casualty insurance |  |  |
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items] |  |  |
Deferred policy acquisition costs | 244 | 322 | 299
Reserves for future policy benefits, claims and unpaid losses and LAE | 10,392 | 10,232 | 9,741
Unearned premiums | 2,803 | 2,830 | 2,595
Net earned premiums | 5,099 | 5,185 | 4,865
Net investment income | 399 | 472 | 438
Benefits, claims, losses and settlement expenses | 3,271 | 3,271 | 3,003
Amortization of deferred policy acquisition costs | 615 | 721 | 644
Other operating expenses | 1,036 | 1,027 | 957
Net written premiums (excluding life) | 5,013 | 5,342 | 5,023
Annuity |  |  |
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items] |  |  |
Deferred policy acquisition costs | 287 | 696 | 1,360
Reserves for future policy benefits, claims and unpaid losses and LAE | 42,573 | 40,406 | 36,616
Net investment income | 1,699 | 1,792 | 1,638
Benefits, claims, losses and settlement expenses | 1,192 | 1,151 | 998
Amortization of deferred policy acquisition costs | 247 | 198 | 212
Other operating expenses | 220 | 201 | 192
Other |  |  |
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items] |  |  |
Deferred policy acquisition costs | 15 | 19 | 23
Reserves for future policy benefits, claims and unpaid losses and LAE | 607 | 612 | 635
Net earned premiums | 19 | 22 | 24
Net investment income | 34 | 39 | 18
Benefits, claims, losses and settlement expenses | 40 | 36 | 40
Amortization of deferred policy acquisition costs | 4 | 4 | 4
Other operating expenses | 436 | 520 | 461
Net written premiums (excluding life) | $ 4 | $ 3 | $ 3

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