Stockholders' Equity - Schedule of Shares Repurchased (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
2019 Program
Equity, Class of Treasury Stock [Line Items]
Shares repurchased and retired (in shares)	2	15
Aggregate value	$ 114	$ 763
Average price per share (in usd per share)	$ 66.58	$ 49.86
Remaining authorization	$ 503	$ 737
2018 Program
Equity, Class of Treasury Stock [Line Items]
Shares repurchased and retired (in shares)		8
Aggregate value		$ 464
Average price per share (in usd per share)		$ 59.47
Remaining authorization		$ 0