Investments - Composition of Current and Past Due Mortgage Loans on Real Estate (Details) - USD ($)	Mar. 31, 2025	Dec. 31, 2024
Loans and Leases Receivable Disclosure [Line Items]
Allowance for credit losses	$ (154,000,000)	$ (152,000,000)
Unamortized premium (discount)	86,000,000	77,000,000
Mark-to-market gains (losses)	(32,000,000)	(31,000,000)
Total carrying value	21,558,000,000	21,083,000,000
Loans with fair value option in non-accrual, amortized cost	30,000,000	30,000,000
Loans with fair value option in non-accrual	21,000,000	21,000,000
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	21,397,000,000	20,954,000,000
30 to 59 days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	97,000,000	77,000,000
60 to 89 days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	29,000,000	33,000,000
90 or more days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	135,000,000	125,000,000
Commercial
Loans and Leases Receivable Disclosure [Line Items]
Allowance for credit losses	(98,000,000)	(99,000,000)
Unamortized premium (discount)	(5,000,000)	(6,000,000)
Mark-to-market gains (losses)	(32,000,000)	(31,000,000)
Total carrying value	17,514,000,000	17,472,000,000
Commercial \| Current
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	17,602,000,000	17,567,000,000
Commercial \| 30 to 59 days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	13,000,000	6,000,000
Commercial \| 60 to 89 days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	3,000,000	0
Commercial \| 90 or more days past due
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	31,000,000	35,000,000
Residential mortgage loans on real estate
Loans and Leases Receivable Disclosure [Line Items]
Allowance for credit losses	(56,000,000)	(53,000,000)
Unamortized premium (discount)	91,000,000	83,000,000
Mark-to-market gains (losses)	0	0
Total carrying value	4,044,000,000	3,611,000,000
Residential mortgage loans on real estate \| Current
Loans and Leases Receivable Disclosure [Line Items]
Mortgage loans on real estate, gross	3,795,000,000	3,387,000,000
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	84,000,000	71,000,000
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	26,000,000	33,000,000
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	$ 104,000,000	$ 90,000,000

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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-Name Accounting Standards Codification
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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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This item represents the aggregate fair value of loans held as assets that are in nonaccrual status for which the fair value option has been elected, if the entity's policy is to recognize interest income separately from other changes in fair value.

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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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Amortized cost excluding accrued interest, before allowance for credit loss, of 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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