Investments (Net Investment Income - Narrative) (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 Investment Income	$ 1,309	$ 1,258	$ 3,836	$ 3,757
Trading securities (1)
Net Investment Income [Line Items]
Investment gains (losses) on trading securities still held	7	0	7	0
Other limited partnership interests
Net Investment Income [Line Items]
Net Investment Income	$ 102	$ 65	$ 221	$ 259