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Business Segments (Balance Sheet Information) (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Segment Reporting Information [Line Items] |  |  |
Reinsurance receivables | $ 6,072 | $ 5,434 | $ 5,438
Insurance receivables | 3,697 | 3,470 | 3,187
Deferred acquisition costs | 959 | 896 | 806
Goodwill | 145 | 146 | 144
Deferred non-insurance warranty acquisition expense | 3,525 | 3,661 | 3,671
Insurance reserves |  |  |
Claim and claim adjustment expenses | 24,976 | 23,304 | 22,120
Unearned premiums | 7,346 | 6,933 | 6,374
Future policy benefits |  |  | 13,480
Future policy benefits | 13,158 | 13,959 | 13,480
Deferred non-insurance warranty revenue | 4,530 | 4,694 | 4,714
Operating Segments | Specialty |  |  |
Segment Reporting Information [Line Items] |  |  |
Reinsurance receivables | 1,405 | 1,281 | 1,384
Insurance receivables | 1,062 | 1,053 | 1,082
Deferred acquisition costs | 427 | 392 | 381
Goodwill | 117 | 117 | 117
Deferred non-insurance warranty acquisition expense | 3,525 | 3,661 | 3,671
Insurance reserves |  |  |
Claim and claim adjustment expenses | 7,426 | 7,131 | 6,878
Unearned premiums | 3,275 | 3,227 | 3,193
Future policy benefits |  |  | 0
Future policy benefits | 0 | 0 |
Deferred non-insurance warranty revenue | 4,530 | 4,694 | 4,714
Operating Segments | Commercial |  |  |
Segment Reporting Information [Line Items] |  |  |
Reinsurance receivables | 1,710 | 1,218 | 1,062
Insurance receivables | 2,219 | 2,024 | 1,728
Deferred acquisition costs | 405 | 371 | 321
Goodwill | 0 | 0 | 0
Deferred non-insurance warranty acquisition expense | 0 | 0 | 0
Insurance reserves |  |  |
Claim and claim adjustment expenses | 11,336 | 10,103 | 9,395
Unearned premiums | 3,252 | 2,858 | 2,425
Future policy benefits |  |  | 0
Future policy benefits | 0 | 0 |
Deferred non-insurance warranty revenue | 0 | 0 | 0
Operating Segments | International |  |  |
Segment Reporting Information [Line Items] |  |  |
Reinsurance receivables | 539 | 468 | 414
Insurance receivables | 410 | 388 | 369
Deferred acquisition costs | 127 | 133 | 104
Goodwill | 28 | 29 | 27
Deferred non-insurance warranty acquisition expense | 0 | 0 | 0
Insurance reserves |  |  |
Claim and claim adjustment expenses | 2,920 | 2,709 | 2,403
Unearned premiums | 727 | 749 | 653
Future policy benefits |  |  | 0
Future policy benefits | 0 | 0 |
Deferred non-insurance warranty revenue | 0 | 0 | 0
Operating Segments | Life & Group |  |  |
Segment Reporting Information [Line Items] |  |  |
Reinsurance receivables | 82 | 93 | 101
Insurance receivables | 4 | 5 | 8
Deferred acquisition costs | 0 | 0 | 0
Goodwill | 0 | 0 | 0
Deferred non-insurance warranty acquisition expense | 0 | 0 | 0
Insurance reserves |  |  |
Claim and claim adjustment expenses | 622 | 675 | 695
Unearned premiums | 92 | 99 | 103
Future policy benefits |  |  | 13,480
Future policy benefits | 13,158 | 13,959 |
Deferred non-insurance warranty revenue | 0 | 0 | 0
Operating Segments | Corporate & Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Reinsurance receivables | 2,336 | 2,374 | 2,477
Insurance receivables | 2 | 0 | 0
Deferred acquisition costs | 0 | 0 | 0
Goodwill | 0 | 0 | 0
Deferred non-insurance warranty acquisition expense | 0 | 0 | 0
Insurance reserves |  |  |
Claim and claim adjustment expenses | 2,672 | 2,686 | 2,749
Unearned premiums | 0 | 0 | 0
Future policy benefits |  |  | 0
Future policy benefits | 0 | 0 |
Deferred non-insurance warranty revenue | 0 | 0 | 0
Eliminations |  |  |
Segment Reporting Information [Line Items] |  |  |
Reinsurance receivables | 0 | 0 | 0
Insurance receivables | 0 | 0 | 0
Deferred acquisition costs | 0 | 0 | 0
Goodwill | 0 | 0 | 0
Deferred non-insurance warranty acquisition expense | 0 | 0 | 0
Insurance reserves |  |  |
Claim and claim adjustment expenses | 0 | 0 | 0
Unearned premiums | 0 | 0 | 0
Future policy benefits |  |  | 0
Future policy benefits | 0 | 0 |
Deferred non-insurance warranty revenue | $ 0 | $ 0 | $ 0

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- Definition Amount, before effect of reinsurance, of present value of future benefit to be paid to or on behalf of policyholder and related expense less present value of future net premium receivable under insurance contract. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-6 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 65 -Paragraph 2 -Subparagraph (g)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480016/944-40-65-2 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(13)(a)(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 29E -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-29E Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-6 + Details
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