Investments - Residential Mortgage Loans by Year of Origination (Details) - Residential - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 1,260	$ 517
Year two	797	555
Year three	524	483
Year four	448	81
Year five	72	112
Year six and prior	150	57
Total	3,251	1,805
Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	1,260	515
Year two	790	533
Year three	498	465
Year four	435	78
Year five	70	99
Year six and prior	136	53
Total	3,189	1,743
Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	0	2
Year two	7	22
Year three	26	18
Year four	13	3
Year five	2	13
Year six and prior	14	4
Total	$ 62	$ 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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