Investments - Investment Gains and Losses (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Investments [Abstract]
Net investment gains (losses), before income taxes	$ 52	$ (48)	$ 50	$ (1,884)

Gains (losses) based on specifically identified assets and resulting from sales, investment asset write-downs, changes in the fair value of certain derivatives and equity securities and changes in allowances for credit losses on debt securities and commercial mortgage loan investments

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration