Stockholders' Equity - Stock Repurchase Program (Details) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Mar. 31, 2020	Jun. 30, 2021	Apr. 30, 2021	Nov. 05, 2020
Subsidiary, Sale of Stock [Line Items]
Additional shares authorized for repurchase					200,000,000
Value of shares repurchased	$ 105,786,000	$ 145,806,000	$ (29,203,000)
Treasury stock at cost
Subsidiary, Sale of Stock [Line Items]
Number of shares repurchased				(17,949,000)
Value of shares repurchased	$ 105,786,000	$ 145,806,000	$ (29,203,000)
Common Class A
Subsidiary, Sale of Stock [Line Items]
Amount authorized to be repurchased					$ 500,000,000
Common Class A | Common Stock
Subsidiary, Sale of Stock [Line Items]
Number of shares repurchased	(7,548,000)	(10,401,000)	(1,619,000)
Common Class A | Treasury stock at cost
Subsidiary, Sale of Stock [Line Items]
Amount authorized to be repurchased						$ 300,000
Treasury stock at cost
Subsidiary, Sale of Stock [Line Items]
Value of shares repurchased				$ (251,592,000)