Fair Value Measurements - Gains or losses recorded related to fair value option (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Fair Value, Option, Quantitative Disclosures
Total gain (loss)	$ 907	$ 680	$ 458
Total liabilities
Fair Value, Option, Quantitative Disclosures
Total gain (loss)	(1)	4	3
Policyholder contract deposits
Fair Value, Option, Quantitative Disclosures
Total gain (loss)	(1)	4	3
Total assets
Fair Value, Option, Quantitative Disclosures
Total gain (loss)	908	676	455
Other bond securities
Fair Value, Option, Quantitative Disclosures
Total gain (loss)	463	369	340
Alternative investments
Fair Value, Option, Quantitative Disclosures
Total gain (loss)	$ 445	$ 307	$ 115

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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