Investments - Realized capital gains and losses by transaction type (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Investments [Abstract]
Sales	$ (175)	$ 80	$ (605)	$ 441
Credit losses	(6)	(12)	(30)	2
Valuation change of equity investments	(285)	(9)	(1,421)	321
Valuation change and settlements of derivatives	299	46	889	54
Net gains (losses) on investments and derivatives	$ (167)	$ 105	$ (1,167)	$ 818