Investments (Fixed Maturity Securities AFS - Sales and Disposals and Credit Loss) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Proceeds	$ 7,241	$ 6,352
Gross investment gains	86	156
Gross investment (losses)	(351)	(312)
Realized gains (losses) on sales and disposals	(265)	(156)
Net credit loss (provision) release (change in ACL recognized in earnings)	24	71
Impairment (losses)	(3)	0
Net credit loss (provision) release and impairment (losses)	21	71
Net investment gains (losses)	(301)	(135)
Equity securities	(22)	(2)
Changes in estimated fair value subsequent to purchase of equity securities still held at the end of the respective periods and recognized in net investment gains (losses)	10	30
Net investment gains (losses)	(12)	28
Fixed Maturity Securities
Debt Securities, Available-for-sale [Line Items]
Net investment gains (losses)	$ (244)	$ (85)

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