Investments (Supplemental Net Investment Gains (Losses)) (Details) - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
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| Net Investment Income [Line Items] | ||
| Equity Securities, FV-NI, Unrealized Gain (Loss) | $ (9) | $ 10 |
| Realized gains (losses) on investments sold or disposed | (242) | (301) |
| Foreign Currency Transaction Gain (Loss), Realized | (132) | 75 |
| Debt and Equity Securities, Realized Gain (Loss) | (71) | (258) |
| Net investment income | ||
| Net Investment Income [Line Items] | ||
| Debt and Equity Securities, Realized Gain (Loss) | 171 | 43 |
| Equity Securities | ||
| Net Investment Income [Line Items] | ||
| Equity Securities, FV-NI, Unrealized Gain (Loss) | $ (11) | $ (10) |
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- Definition Amount of realized gain (loss) on investment in debt and equity securities. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, before tax, of realized gain (loss) from foreign currency transaction. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of realized gain (loss) on investment. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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