CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (PARENTHETICAL) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income tax expense	$ 450	$ 503	$ 170
RETAINED EARNINGS (ACCUMULATED DEFICIT)
Income tax expense		$ (2)	$ 37