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Investments (Supplemental Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Net Investment Income [Line Items]
Net realized investment gains (losses) from sales and disposals of investments	$ 114	$ 26	$ (187)	$ (170)
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)	11	(58)	84	(47)
Income (Loss) from Equity Method Investments	620	201	1,125	687
Net investment income
Net Investment Income [Line Items]
Net realized investment gains (losses) from sales and disposals of investments	92	65	237	199
Debt and Equity Securities, Unrealized Gain (Loss)	514	121	677	840
Debt and Equity Securities, Gain (Loss)	606	186	914	1,039
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)	$ 572	$ 209	$ 803	$ 813

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