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	Sep. 30, 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	937	614
Year two	763	376
Year three	360	928
Year four	867	840
Year five	773	176
Prior	465	340
Total	4,165	3,274
Credit Quality Indicator Prior Year [Abstract]
Year one	937	614
Year two	763	376
Year three	360	928
Year four	867	840
Year five	773	176
Prior	465	340
Total	4,165	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	3,303	2,722
Credit Quality Indicator Prior Year [Abstract]
Total	3,303	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	931	610
Year two	752	368
Year three	353	911
Year four	846	805
Year five	749	162
Prior	425	312
Total	4,056	3,168
Credit Quality Indicator Prior Year [Abstract]
Year one	931	610
Year two	752	368
Year three	353	911
Year four	846	805
Year five	749	162
Prior	425	312
Total	4,056	3,168
30-89 days past due \| Residential Mortgage
Credit Quality Indicator Current Year [Abstract]
Year one	6	1
Year two	6	6
Year three	3	4
Year four	10	6
Year five	3	1
Prior	9	3
Total	37	21
Credit Quality Indicator Prior Year [Abstract]
Year one	6	1
Year two	6	6
Year three	3	4
Year four	10	6
Year five	3	1
Prior	9	3
Total	37	21
90 days or more past due \| Residential Mortgage
Credit Quality Indicator Current Year [Abstract]
Year one	0	3
Year two	5	2
Year three	4	13
Year four	11	29
Year five	21	13
Prior	31	25
Total	72	85
Credit Quality Indicator Prior Year [Abstract]
Year one	0	3
Year two	5	2
Year three	4	13
Year four	11	29
Year five	21	13
Prior	31	25
Total	$ 72	$ 85

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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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