Investments - Composition of Current and Past Due Mortgage Loans on Real Estate (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Financing Receivable, Past Due [Line Items]
Allowance for credit losses	$ (179)	$ (181)
Unamortized premium (discount)	117	106
Mark-to-market gains (losses)	(31)	(33)
Total carrying value	22,692	22,338
Loans with fair value option in non-accrual, amortized cost	30	30
Loans with fair value option in non-accrual	19	20
Loans with fair value option, 90 days past due and still accruing	0	0
Current
Financing Receivable, Past Due [Line Items]
Mortgage loans on real estate, gross	22,460	22,134
30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Mortgage loans on real estate, gross	92	94
60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Mortgage loans on real estate, gross	29	39
90 or more days past due
Financing Receivable, Past Due [Line Items]
Mortgage loans on real estate, gross	204	179
Commercial
Financing Receivable, Past Due [Line Items]
Allowance for credit losses	(115)	(112)
Unamortized premium (discount)	(9)	(9)
Mark-to-market gains (losses)	(32)	(33)
Total carrying value	17,351	17,393
Commercial \| Current
Financing Receivable, Past Due [Line Items]
Mortgage loans on real estate, gross	17,468	17,506
Commercial \| 30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Mortgage loans on real estate, gross	3	1
Commercial \| 60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Mortgage loans on real estate, gross	0	5
Commercial \| 90 or more days past due
Financing Receivable, Past Due [Line Items]
Mortgage loans on real estate, gross	36	35
Residential
Financing Receivable, Past Due [Line Items]
Allowance for credit losses	(64)	(69)
Unamortized premium (discount)	126	115
Mark-to-market gains (losses)	1	0
Total carrying value	5,341	4,945
Residential \| Current
Financing Receivable, Past Due [Line Items]
Mortgage loans on real estate, gross	4,992	4,628
Residential \| 30 to 59 days past due
Financing Receivable, Past Due [Line Items]
Mortgage loans on real estate, gross	89	93
Residential \| 60 to 89 days past due
Financing Receivable, Past Due [Line Items]
Mortgage loans on real estate, gross	29	34
Residential \| 90 or more days past due
Financing Receivable, Past Due [Line Items]
Mortgage loans on real estate, gross	$ 168	$ 144

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.

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

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