Earnings Per Share - Schedule of Reconciliation of Numerators and Denominators Used to Calculate Basic EPS and Diluted EPS (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Earnings Per Share [Abstract]
Net income	$ 23	$ 181	$ 162	$ 348
Weighted average shares of common stock outstanding	113	123	114	124
Dilutive effect of stock-based awards	1	1	1	1
Diluted weighted average shares of common stock outstanding	114	124	115	125
Basic earnings per share attributable to common stockholders (USD per share)	$ 0.20	$ 1.47	$ 1.42	$ 2.81
Diluted earnings per share attributable to common stockholders (USD per share)	$ 0.20	$ 1.46	$ 1.41	$ 2.78