Stock Repurchases - USD ($)		3 Months Ended	9 Months Ended
		Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Mar. 05, 2020
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased, shares			2,277,817	725,220
Common stock repurchased, value		$ 704,200,000	$ 1,093,900,000	$ 307,100,000
Increase in number of shares authorized for repurchase					2,000,000
Remaining number of shares authorized for repurchase		2,231,859	2,231,859
Open Market [Member]
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased, shares	[1]		2,270,751	710,157
Common stock repurchased, value	[1]		$ 1,091,200,000	$ 300,600,000
Other [Member]
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased, shares	[2]		7,066	15,063
Common stock repurchased, value	[2]		$ 2,700,000	$ 6,500,000

[1] Represents repurchases under authorizations by the board of directors for the repurchase of shares by us from time to time in the open market through privately negotiated transactions, through block trades, pursuant to trading plans adopted in accordance with Rule 10b5-1 under the Securities Exchange Act of 1934 or otherwise. On September 28, 2021, the board of directors authorized the repurchase of up to two million shares of our common stock in addition to the board’s prior authorizations. As of September 30, 2021, we had authorization to repurchase 2,231,859 shares of our common stock.

[2] Represents shares of common stock released to us by team members as payment of tax withholdings upon the vesting of restricted stock and restricted stock units and the conversion of restricted stock units to common stock.