Derivatives (Details) - OTC derivatives $ in Millions	Dec. 31, 2025 USD ($) counterparty	Dec. 31, 2024 USD ($)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Net Liability Position, Aggregate Fair Value	$ 0	$ 0
Collateral Already Posted, Aggregate Fair Value	$ 0	$ 0
Net uncollateralized exposure to derivative counterparties \| SP Equivalent Investment Grade Rating
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of counterparties \| counterparty	3

Represents number of counterparties with respect to mortgage seller/servicers, mortgage insurers, bond insurers, and cash and other investments.

No definition available.

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- Definition

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

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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.

+ References

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
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