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Investment Information - Other investments (Details) - USD ($) $ in Millions | Dec. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Other investments | $ 3,136 | $ 3,066
Other investments |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Other investments | 1,957 | 2,135
Fixed maturities |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Other investments | 1,110 | 854
Equity securities |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Other investments | 5 | 7
Short-term investments |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |
Other investments | $ 64 | $ 70

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