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, 2024	Dec. 31, 2023
Amortized Cost of Non-Accrual Loans [Abstract]
Amortized cost of loans on non-accrual	$ 66	$ 57
Residential mortgage loans
Credit Quality Indicator Current Year [Abstract]
2024	56	373
2023	404	995
2022	997	877
2021	895	208
2020	203	204
Prior	389	195
Credit Quality Indicator Prior Year [Abstract]
2023	56	373
2022	404	995
2021	997	877
2020	895	208
2019	203	204
Prior	389	195
Total	2,944	2,852
Amortized Cost of Non-Accrual Loans [Abstract]
Amortized cost of loans on non-accrual	66	57
Commercial mortgage loans
Credit Quality Indicator Current Year [Abstract]
Total	2,563	2,528
Credit Quality Indicator Prior Year [Abstract]
Total	2,563	2,550
Amortized Cost of Non-Accrual Loans [Abstract]
Amortized cost of loans on non-accrual	0	0
Current (less than 30 days past due) \| Residential mortgage loans
Credit Quality Indicator Current Year [Abstract]
2024	56	373
2023	402	985
2022	984	854
2021	874	192
2020	185	183
Prior	361	192
Credit Quality Indicator Prior Year [Abstract]
2023	56	373
2022	402	985
2021	984	854
2020	874	192
2019	185	183
Prior	361	192
Total	2,862	2,779
Current (less than 30 days past due) \| Commercial mortgage loans
Credit Quality Indicator Current Year [Abstract]
Total	2,563	2,528
30-89 days past due \| Residential mortgage loans
Credit Quality Indicator Current Year [Abstract]
2024	0	0
2023	1	4
2022	2	7
2021	3	3
2020	6	0
Prior	4	2
Credit Quality Indicator Prior Year [Abstract]
2023	0	0
2022	1	4
2021	2	7
2020	3	3
2019	6	0
Prior	4	2
Total	16	16
30-89 days past due \| Commercial mortgage loans
Credit Quality Indicator Current Year [Abstract]
Total	0	0
90 Days or more past due \| Residential mortgage loans
Credit Quality Indicator Current Year [Abstract]
2024	0	0
2023	1	6
2022	11	16
2021	18	13
2020	12	21
Prior	24	1
Credit Quality Indicator Prior Year [Abstract]
2023	0	0
2022	1	6
2021	11	16
2020	18	13
2019	12	21
Prior	24	1
Total	66	57
90 Days or more past due \| Commercial mortgage loans
Credit Quality Indicator Current Year [Abstract]
Total	$ 0	$ 0

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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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