Condensed Consolidated Statements Of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 473	$ 566
Other comprehensive income:
Change in gross unrealized investment gains/losses	(92)	196
Effect of income taxes	22	(45)
Total change in unrealized investment gains/losses, net of tax	(70)	151
Reclassification adjustment for net realized gains	(45)	0
Effect of income taxes	10	0
Total reclassification adjustment, net of tax	(35)	0
Other comprehensive (loss) income, net of tax	(105)	151
Comprehensive loss attributable to equity method investments	(3)	(2)
Comprehensive income	$ 365	$ 715