Fair Value of Financial Instruments - Schedule of Mortgage Loans With Election of Fair Value Option (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value	$ 263	$ 288
Commercial
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value	263	288
Aggregate contractual principal	$ 297	$ 326

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/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 30
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-30

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 31
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-31

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 32
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-32

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