Fair Value of Financial Instruments - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	$ 45,762	$ 44,902
U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	27,046	26,771
Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	7,191	7,327
Level 2
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	42,691	42,109
Level 2 \| Other invested assets \| Nonrecurring fair value
Fair Value of Financial Instruments [Line Items]
Real estate owned	29	25
Level 2 \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	25,089	24,821
Level 2 \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	6,442	6,652
Level 3
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	3,071	2,793
Level 3 \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	1,957	1,950
Level 3 \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	$ 749	$ 675
Total 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%
Total fixed maturity securities \| Level 2 \| Third-Party Pricing Services \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	$ 23,330
Total fixed maturity securities \| Level 2 \| Third-Party Pricing Services \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	5,611
Total fixed maturity securities \| Level 2 \| Internal models \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	1,759
Total fixed maturity securities \| Level 2 \| Internal models \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	831
Total fixed maturity securities \| Level 3 \| Third-Party Pricing Services
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	241
Total fixed maturity securities \| Level 3 \| Broker Quotes
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	184
Total fixed maturity securities \| Level 3 \| Internal models
Fair Value of Financial Instruments [Line Items]
Fixed maturity securities	$ 2,646
Limited partnerships \| Fair Value Measured at Net Asset Value Per Share \| Minimum
Fair Value of Financial Instruments [Line Items]
Liquidation period	5 years
Contractual period	10 years
Limited partnerships \| Fair Value Measured at Net Asset Value Per Share \| 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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- 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
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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

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
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