Investments - Residential Mortgage Loans by Year of Origination (Details) - Residential - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 54	$ 517
Year two	670	555
Year three	548	483
Year four	475	81
Year five	78	112
Year six and prior	162	57
Total	1,987	1,805
Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	54	515
Year two	665	533
Year three	525	465
Year four	459	78
Year five	76	99
Year six and prior	147	53
Total	1,926	1,743
Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	2
Year two	5	22
Year three	23	18
Year four	16	3
Year five	2	13
Year six and prior	15	4
Total	$ 61	$ 62

Amortized cost, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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