Investments - Composition of Current and Past Due Mortgage Loans on Real Estate (Details) - USD ($)	Sep. 30, 2024	Dec. 31, 2023
Loans and Leases Receivable Disclosure [Line Items]
Allowance for credit losses	$ (170,000,000)	$ (114,000,000)
Unamortized premium (discount)	57,000,000	36,000,000
Mark-to-market gains (losses)	(33,000,000)	(38,000,000)
Total carrying value	20,856,000,000	18,963,000,000
Loans with fair value option in non-accrual, amortized cost	30,000,000	1,000,000
Loans with fair value option in non-accrual	21,000,000	1,000,000
Loans with fair value option, 90 days past due and still accruing	0	0
Current
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	20,748,000,000	18,921,000,000
30 to 59 days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	119,000,000	89,000,000
60 to 89 days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	20,000,000	9,000,000
90 or more days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	115,000,000	60,000,000
Commercial
Loans and Leases Receivable Disclosure [Line Items]
Allowance for credit losses	(123,000,000)	(86,000,000)
Unamortized premium (discount)	(16,000,000)	(7,000,000)
Mark-to-market gains (losses)	(33,000,000)	(37,000,000)
Total carrying value	17,652,000,000	17,187,000,000
Commercial \| Current
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	17,684,000,000	17,256,000,000
Commercial \| 30 to 59 days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	85,000,000	61,000,000
Commercial \| 60 to 89 days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	0	0
Commercial \| 90 or more days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	55,000,000	0
Residential mortgage loans on real estate
Loans and Leases Receivable Disclosure [Line Items]
Allowance for credit losses	(47,000,000)	(28,000,000)
Unamortized premium (discount)	73,000,000	43,000,000
Mark-to-market gains (losses)	0	(1,000,000)
Total carrying value	3,204,000,000	1,776,000,000
Residential mortgage loans on real estate \| Current
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	3,064,000,000	1,665,000,000
Residential mortgage loans on real estate \| 30 to 59 days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	34,000,000	28,000,000
Residential mortgage loans on real estate \| 60 to 89 days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	20,000,000	9,000,000
Residential mortgage loans on real estate \| 90 or more days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	$ 60,000,000	$ 60,000,000

Fair Value, Option, Loans Held As Assets, Amortized Cost, Aggregate Amount In Nonaccrual Status

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This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected.

+ References

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This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount of unamortized purchase premium (discount) on financing receivable. Excludes financing receivable covered under loss sharing agreement.

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