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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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Amount of investments classified as other.

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