Stock Repurchases (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Feb. 13, 2017
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased, shares		2,884,126	1,282,166	712,448
Common stock repurchased, value		$ 1,471.8	$ 480.8	$ 300.4
Increase in number of shares authorized for repurchase					2,000,000
Number of shares authorized for repurchase		1,625,550
Open Market [Member]
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased, shares	[1]	2,877,060	1,267,103	669,752
Common stock repurchased, value	[1]	$ 1,469.1	$ 474.3	$ 282.2
Other [Member]
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased, shares	[2]	7,066	15,063	42,696
Common stock repurchased, value	[2]	$ 2.7	$ 6.5	$ 18.2

[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 December 31, 2021, we had authorization to repurchase 1,625,550 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.