Investments (Securities Lending and Repurchase Agreements) (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
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| Securities Financing Transaction [Line Items] | ||
| Cash collateral on deposit from counterparties | $ 12,552 | $ 12,198 |
| Reinvestment portfolio - estimated fair value | 12,481 | 12,082 |
| Estimated fair value | ||
| Securities Financing Transaction [Line Items] | ||
| Securities loaned | 12,169 | 11,866 |
| Securities Sold under Agreements to Repurchase | 3,124 | 3,002 |
| Repurchase Agreements | ||
| Securities Financing Transaction [Line Items] | ||
| Cash collateral on deposit from counterparties | 3,075 | 2,975 |
| Reinvestment portfolio - estimated fair value | $ 3,043 | $ 2,948 |
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- Definition This element represents the estimated fair value of the securities lending reinvestment portfolio. No definition available.
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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. No definition available.
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- Definition Amount, after the effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Carrying amount of liabilities associated with financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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