Investments - Roll Forward of Credit Losses in the Investment Portfolio (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Roll Forward of Credit Losses in the Investment Portfolio | ||||
| Balance, beginning of period | $ 72 | $ 47 | $ 54 | $ 60 |
| Additions for securities for which credit losses were not previously recognized | 1 | 1 | 18 | 11 |
| Additions for purchases of securities accounted for as purchased financial assets with credit deterioration | 2 | 0 | 2 | 0 |
| Additions (reductions) for securities for which credit losses were previously recognized | 12 | 11 | 20 | 13 |
| Write-offs charged against the allowance | (5) | (5) | (12) | (30) |
| Balance, end of period | $ 82 | $ 54 | $ 82 | $ 54 |
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount excluding accrued interest, of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, excluding accrued interest, of credit loss expense on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) with no credit loss previously recorded. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, excluding accrued interest, of credit loss expense (reversal of expense) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) with previously recorded allowance and not intended to be sold and not more likely than not will be required to sell before recovery of amortized cost basis. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, excluding accrued interest, of decrease in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from writeoff. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, excluding accrued interest, of allowance for credit loss at acquisition date of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) purchased with credit deterioration. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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