Stock Repurchases - USD ($) $ in Millions		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Mar. 05, 2020
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased, shares		725,220	268,611
Common stock repurchased, value		$ 307.1	$ 109.2
Increase in number of shares authorized for repurchase				3,000,000
Remaining number of shares authorized for repurchase		3,059,556
Open Market [Member]
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased, shares	[1]	710,157	225,915
Common stock repurchased, value	[1]	$ 300.6	$ 91.0
Other [Member]
Equity, Class of Treasury Stock [Line Items]
Common stock repurchased, shares	[2]	15,063	42,696
Common stock repurchased, value	[2]	$ 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 or in privately negotiated transactions. On March 5, 2020, the board of directors authorized the repurchase of up to three million shares of our common stock in addition to the board’s prior authorizations. As of September 30, 2020, we had authorization to repurchase 3,059,556 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.