Investments - Schedule of Portfolio Composition (Details) - USD ($) $ in Millions |
Sep. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Investments [Abstract] | ||
| Fixed income securities, at fair value | $ 60,246 | $ 59,115 |
| Equity securities, at fair value | 10,172 | 8,398 |
| Mortgage loans, net | 1,040 | 879 |
| Limited partnership interests | 9,058 | 8,844 |
| Short-term investments, at fair value | 5,779 | 4,887 |
| Other investments, net | 1,080 | 1,114 |
| Total investments | $ 87,375 | $ 83,237 |
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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). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all investments. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- References No definition available.
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- Definition Amount of investment in equity method investee and investment in and advance to affiliate. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of investments classified as other. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of short-term investments classified as other. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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