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Fair Value Measurements - Difference Between the Aggregate Fair Value and the Aggregate Unpaid Principal Balance for Residential Mortgage Loans Measured at Fair Value (Details) - Residential mortgage loans - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Aggregate Fair Value |  |
Residential mortgage loans measured at fair value | $ 672 | $ 682
Past due loans of 30-89 days | 2 | 1
Past due loans of 90 days or more | 1 | 1
Nonaccrual loans | 3 | 2
Aggregate Unpaid Principal Balance |  |
Residential mortgage loans measured at fair value | 668 | 693
Past due loans of 30-89 days | 2 | 1
Past due loans of 90 days or more | 1 | 1
Nonaccrual loans | $ 3 | $ 2

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- Definition Fair Value, Option, Loans Held as Assets, 30-89 Days Past Due + References No definition available. + Details
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- Definition Fair value option loans held as assets 90 days or more past due aggregate unpaid principal. + References No definition available. + Details
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- Definition Fair value option loans held as assets 90 days or more past due aggregate unpaid principal. + References No definition available. + Details
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- Definition Fair value option loans held as assets aggregate unpaid principal balance abstract. + References No definition available. + Details
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- Definition Fair value option loans held as assets amount in non accrual status aggregate unpaid principal. + References No definition available. + Details
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- Definition Fair value portion loans receivable disclosure. + References No definition available. + Details
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- Definition Mortgage Loans, Aggregate Unpaid Principal + References No definition available. + Details
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Balance Type: | debit
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- Definition This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (e)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-28 + Details
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- Definition This item represents the aggregate fair value of loans held as assets that are in nonaccrual status for which the fair value option has been elected, if the entity's policy is to recognize interest income separately from other changes in fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 28 -Subparagraph (e)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-28 + Details
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- Details
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