Fair Value of Financial Instruments - Schedule of Mortgage Loans With Election of Fair Value Option (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value	$ 230	$ 232
Commercial
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value	230	232
Aggregate contractual principal	$ 263	$ 263

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.

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