Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Numerator:
Net income available to common stockholders	$ 367	$ 203
Denominator:
Denominator for basic earnings per share—weighted-average common shares (in shares)	72,372	72,338
Effect of dilutive securities:
Denominator for diluted earnings per share—adjusted weighted-average common shares (in shares)	72,684	72,674
Basic earnings per share (in dollars per share)	$ 5.07	$ 2.81
Diluted earnings per share (in dollars per share)	$ 5.05	$ 2.80
Employee stock options
Effect of dilutive securities:
Effect of dilutive securities (in shares)	4	6
Restricted stock units
Effect of dilutive securities:
Effect of dilutive securities (in shares)	308	330