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	Jun. 30, 2024	Dec. 31, 2023
Amortized Cost of Non-Accrual Loans [Abstract]
Amortized cost of loans on non-accrual	$ 62	$ 57
Residential Mortgage Loans
Credit Quality Indicator Current Year [Abstract]
2024	142	373
2023	378	995
2022	981	877
2021	871	208
2020	194	204
Prior	363	195
Credit Quality Indicator Prior Year [Abstract]
2023	142	373
2022	378	995
2021	981	877
2020	871	208
2019	194	204
Prior	363	195
Total	2,929	2,852
Amortized Cost of Non-Accrual Loans [Abstract]
Amortized cost of loans on non-accrual	62	57
Commercial Mortgage Loans
Credit Quality Indicator Current Year [Abstract]
Total	2,574	2,528
Credit Quality Indicator Prior Year [Abstract]
Total	2,574	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	142	373
2023	374	985
2022	964	854
2021	836	192
2020	181	183
Prior	330	192
Credit Quality Indicator Prior Year [Abstract]
2023	142	373
2022	374	985
2021	964	854
2020	836	192
2019	181	183
Prior	330	192
Total	2,827	2,779
Current (less than 30 days past due) \| Commercial Mortgage Loans
Credit Quality Indicator Current Year [Abstract]
Total	2,574	2,528
30-89 days past due \| Residential Mortgage Loans
Credit Quality Indicator Current Year [Abstract]
2024	0	0
2023	4	4
2022	7	7
2021	17	3
2020	2	0
Prior	10	2
Credit Quality Indicator Prior Year [Abstract]
2023	0	0
2022	4	4
2021	7	7
2020	17	3
2019	2	0
Prior	10	2
Total	40	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	0	6
2022	10	16
2021	18	13
2020	11	21
Prior	23	1
Credit Quality Indicator Prior Year [Abstract]
2023	0	0
2022	0	6
2021	10	16
2020	18	13
2019	11	21
Prior	23	1
Total	62	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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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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