Investments (Supplemental Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Net Investment Income [Line Items]
Net realized investment gains (losses) from sales and disposals of investments	$ (258)	$ (67)
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
Income (Loss) from Equity Method Investments	267	210
Net investment income
Net Investment Income [Line Items]
Net realized investment gains (losses) from sales and disposals of investments	43	68
Debt and Equity Securities, Unrealized Gain (Loss)	(289)	580
Debt and Equity Securities, Gain (Loss)	(246)	648
Unit-linked investments
Net Investment Income [Line Items]
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)	$ (260)	$ 537