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, 2024	Dec. 31, 2023
Amortized Cost of Non-Accrual Loans [Abstract]
Amortized cost of loans on non-accrual	$ 74	$ 57
Residential Mortgage Loans
Credit Quality Indicator Current Year [Abstract]
2024	393	373
2023	377	995
2022	946	877
2021	858	208
2020	182	204
Prior	349	195
Credit Quality Indicator Prior Year [Abstract]
2023	393	373
2022	377	995
2021	946	877
2020	858	208
2019	182	204
Prior	349	195
Total	3,105	2,852
Amortized Cost of Non-Accrual Loans [Abstract]
Amortized cost of loans on non-accrual	74	57
Commercial Mortgage Loans
Credit Quality Indicator Current Year [Abstract]
Total	2,590	2,528
Credit Quality Indicator Prior Year [Abstract]
Total	2,590	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	387	373
2023	372	985
2022	928	854
2021	822	192
2020	168	183
Prior	317	192
Credit Quality Indicator Prior Year [Abstract]
2023	387	373
2022	372	985
2021	928	854
2020	822	192
2019	168	183
Prior	317	192
Total	2,994	2,779
Current (less than 30 days past due) \| Commercial Mortgage Loans
Credit Quality Indicator Current Year [Abstract]
Total	2,581	2,528
30-89 days past due \| Residential Mortgage Loans
Credit Quality Indicator Current Year [Abstract]
2024	6	0
2023	3	4
2022	9	7
2021	8	3
2020	4	0
Prior	7	2
Credit Quality Indicator Prior Year [Abstract]
2023	6	0
2022	3	4
2021	9	7
2020	8	3
2019	4	0
Prior	7	2
Total	37	16
30-89 days past due \| Commercial Mortgage Loans
Credit Quality Indicator Current Year [Abstract]
Total	9	0
90 days or more past due \| Residential Mortgage Loans
Credit Quality Indicator Current Year [Abstract]
2024	0	0
2023	2	6
2022	9	16
2021	28	13
2020	10	21
Prior	25	1
Credit Quality Indicator Prior Year [Abstract]
2023	0	0
2022	2	6
2021	9	16
2020	28	13
2019	10	21
Prior	25	1
Total	74	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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