Condensed Consolidated Statements of Comprehensive Income (unaudited) (Parenthetical) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Investments with no credit impairment, tax provision (benefit)	$ 31	$ 19	$ 4	$ 44
Investments with credit impairment, tax provision (benefit)	$ 6	$ (12)	$ (7)	$ (12)