Fair Value of Financial Instruments - Additional Information (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	$ 45,264	$ 45,762
U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	26,355	27,046
Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	7,018	7,191
Level 2
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	42,021	42,691
Level 2 \| Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherInvestments \| Nonrecurring fair value
Fair Value of Financial Instruments [Line Items]
Real estate owned	32	29
Level 2 \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	24,360	25,089
Level 2 \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	6,269	6,442
Level 3
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	3,243	3,071
Level 3 \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	1,995	1,957
Level 3 \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	$ 749	$ 749
Fixed maturity securities: \| Level 2 \| Third-Party Pricing Services
Fair Value of Financial Instruments [Line Items]
Percentage of available for sale debt securities	87.00%
Fixed maturity securities: \| Level 2 \| Third-Party Pricing Services \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	$ 22,620
Fixed maturity securities: \| Level 2 \| Third-Party Pricing Services \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	5,508
Fixed maturity securities: \| Level 2 \| Internal models \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	1,740
Fixed maturity securities: \| Level 2 \| Internal models \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	761
Fixed maturity securities: \| Level 3 \| Third-Party Pricing Services
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	290
Fixed maturity securities: \| Level 3 \| Internal models
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	2,740
Fixed maturity securities: \| Level 3 \| Broker Quotes
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	$ 213
Limited partnerships \| Total limited partnerships accounted for at NAV \| Minimum
Fair Value of Financial Instruments [Line Items]
Liquidation period	5 years
Contractual period	10 years
Limited partnerships \| Total limited partnerships accounted for at NAV \| Maximum
Fair Value of Financial Instruments [Line Items]
Liquidation period	10 years
Contractual period	12 years

Fair Value of Financial Instruments [Line Items]

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- Definition

Percent of total fixed maturity securities portfolio priced using third-party pricing sources in determining fair value.

+ References

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Period remaining for expected liquidation by investee of underlying asset of investment measured at net asset value (NAV) per share, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, investment calculated using unit, membership interest, other equity or ownership interest, and alternative investment.

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Period in which restriction on redemption is in effect for investment calculated using net asset value (NAV) per share, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, investment calculated using unit, membership interest, other equity or ownership interest, and alternative investment.

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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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