Stockholders' Equity - Repurchases of Common Stock (Details) - USD ($) $ / shares in Units, shares in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Class of Stock
Stock repurchase program, authorized amount	$ 750,000,000
Payment for shares acquired	$ 33,100,000	$ 433,600,000
Common Stock
Class of Stock
Treasury shares acquired (in shares)	3.7
Payment for shares acquired	$ 33,100,000
Treasury stock price (usd per share)	$ 8.82
Remaining shares authorized for repurchase	$ 210,000,000