Investments - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Investments, Debt and Equity Securities [Abstract]
Amounts loaned under reverse repurchase agreements	$ 117	$ 1,067
Fair value of collateral	$ 510	$ 1,822

Amount, after the effects of master netting arrangements, of funds outstanding loaned in the form of a security resale agreement between the entity and another party for the purchase and resale of identical or substantially the same securities at a date certain for a specified price. Includes purchases of participations in pools of securities that are subject to a resale agreement, assets not subject to a master netting arrangement and not elected to be offset.

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+ Details