Investments - Schedule of Residential Loans Segregated by Aging of Loans (By Year of Origination) and Non-accrual Loans by Amortized Cost (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Amortized Cost of Non-Accrual Loans [Abstract]
Amortized cost of loans on non-accrual	$ 82	$ 94
Residential Mortgage
Credit Quality Indicator Current Year [Abstract]
Year one	311	614
Year two	724	376
Year three	376	928
Year four	903	840
Year five	821	176
Prior	499	340
Credit Quality Indicator Prior Year [Abstract]
Year one	311	614
Year two	724	376
Year three	376	928
Year four	903	840
Year five	821	176
Prior	499	340
Total	3,634	3,274
Amortized Cost of Non-Accrual Loans [Abstract]
Amortized cost of loans on non-accrual	72	85
Commercial Mortgage
Credit Quality Indicator Current Year [Abstract]
Total	2,805	2,722
Credit Quality Indicator Prior Year [Abstract]
Total	2,805	2,722
Amortized Cost of Non-Accrual Loans [Abstract]
Amortized cost of loans on non-accrual	10	9
Current (less than 30 days past due) \| Residential Mortgage
Credit Quality Indicator Current Year [Abstract]
Year one	311	610
Year two	719	368
Year three	372	911
Year four	886	805
Year five	793	162
Prior	460	312
Credit Quality Indicator Prior Year [Abstract]
Year one	311	610
Year two	719	368
Year three	372	911
Year four	886	805
Year five	793	162
Prior	460	312
Total	3,541	3,168
Current (less than 30 days past due) \| Commercial Mortgage
Credit Quality Indicator Current Year [Abstract]
Total	2,795	2,713
30-89 days past due \| Residential Mortgage
Credit Quality Indicator Current Year [Abstract]
Year one	0	1
Year two	4	6
Year three	2	4
Year four	6	6
Year five	2	1
Prior	7	3
Credit Quality Indicator Prior Year [Abstract]
Year one	0	1
Year two	4	6
Year three	2	4
Year four	6	6
Year five	2	1
Prior	7	3
Total	21	21
30-89 days past due \| Commercial Mortgage
Credit Quality Indicator Current Year [Abstract]
Total	0	0
90 days or more past due \| Residential Mortgage
Credit Quality Indicator Current Year [Abstract]
Year one	0	3
Year two	1	2
Year three	2	13
Year four	11	29
Year five	26	13
Prior	32	25
Credit Quality Indicator Prior Year [Abstract]
Year one	0	3
Year two	1	2
Year three	2	13
Year four	11	29
Year five	26	13
Prior	32	25
Total	72	85
90 days or more past due \| Commercial Mortgage
Credit Quality Indicator Current Year [Abstract]
Total	$ 10	$ 9

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated four years prior to current fiscal year. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable originated three years prior to current fiscal year. Excludes net investment in lease.

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