Investments -Realized capital gains and losses by transaction type (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Investments [Abstract]
Sales	$ (832)	$ 578	$ 974
Credit losses	(54)	(42)	(32)
Valuation change of equity investments	(1,060)	499	96
Valuation change and settlements of derivatives	874	49	49
Net gains (losses) on investments and derivatives	$ (1,072)	$ 1,084	$ 1,087