Investments - Residential Mortgage Loans by Year of Origination (Details) - Residential - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	$ 1,909	$ 517
Year two	573	555
Year three	525	483
Year four	438	81
Year five	69	112
Year six and prior	150	57
Total	3,664	1,805
Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	1,895	515
Year two	557	533
Year three	492	465
Year four	427	78
Year five	65	99
Year six and prior	136	53
Total	3,572	1,743
Nonperforming
Financing Receivable, Credit Quality Indicator [Line Items]
Year one	14	2
Year two	16	22
Year three	33	18
Year four	11	3
Year five	4	13
Year six and prior	14	4
Total	$ 92	$ 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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