Fair Value of Financial Instruments - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2026	Dec. 31, 2025
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	$ 45,095	$ 45,762
U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	26,509	27,046
Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	7,045	7,191
Level 2
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	42,072	42,691
Level 2 \| Other invested assets \| Nonrecurring fair value
Fair Value of Financial Instruments [Line Items]
Real estate owned	30	29
Level 2 \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	24,621	25,089
Level 2 \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	6,308	6,442
Level 3
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	3,023	3,071
Level 3 \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	1,888	1,957
Level 3 \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	$ 737	$ 749
Fixed maturity securities: \| Level 2 \| Third-Party Pricing Services
Fair Value of Financial Instruments [Line Items]
Percentage of available for sale debt securities	88.00%
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	$ 22,854
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	5,530
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	1,767
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	778
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	248
Fixed maturity securities: \| Level 3 \| Internal models
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	2,605
Fixed maturity securities: \| Level 3 \| Broker Quotes
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities available-for-sale, at fair value	$ 170
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

No definition available.

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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- Definition

Remaining period of expected liquidation by investee of underlying asset of investment measured at net asset value per share or unit. In 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-107

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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Period when redemption restriction has been in effect for investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-3

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-Topic 310
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