Derivative Instruments and Hedging Activities - Narrative (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
Dec. 22, 2025 |
Jun. 28, 2024 |
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| Derivative [Line Items] | ||||
| Loss protection fee percentage | 4.94% | 7.95% | ||
| Reclaim cash collateral | $ 34 | $ 36 | ||
| Obligation to return cash collateral | 122 | $ 62 | ||
| Interest Rate Swap | Financial Institution Counterparties | ||||
| Derivative [Line Items] | ||||
| Notional amount | $ 1,100 | |||
| Credit Default Swap | Residential Real Estate | ||||
| Derivative [Line Items] | ||||
| Notional amount | $ 80 | $ 1,700 | ||
| Credit Default Swap | Derivatives Not Designated as Hedging Instruments | ||||
| Derivative [Line Items] | ||||
| Notional amount | $ 80 | $ 87 | ||
| Derivative, notional amount, percent of reference pool | 12.50% | 5.00% | ||
| Credit Default Swap, Buying Protection | Derivatives Not Designated as Hedging Instruments | ||||
| Derivative [Line Items] | ||||
| Notional amount | $ 87 |
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- Definition Derivative, Notional Amount, Percent Of Reference Pool No definition available.
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- Definition Loss Protection Fee No definition available.
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- Definition Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of right to receive securities collateral under master netting arrangements that have not been offset against derivative liabilities. 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/2009/role/commonPracticeRef
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- Definition Nominal or face amount used to calculate payment on derivative. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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