Consolidated Statement of Stockholders' Equity - USD ($) $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Paid-in Capital	Accumulated Deficit	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Loss
Beginning balance (in shares) at Dec. 31, 2020			141,900,000
Beginning balance at Dec. 31, 2020	$ 1,297.1	$ 19.2	$ 1.4	$ 3,204.9	$ (1,813.4)	$ 19.2	$ (95.8)
Shareholders' Equity (Deficit) [Roll Forward]
Net income	506.7				506.7
Equity-based compensation expense	36.4			36.4
Stock option exercises (in shares)			900,000
Stock option exercises	41.8			41.8
Coworker Stock Purchase Plan (in shares)			100,000
Coworker Stock Purchase Plan	10.4			10.4
Repurchases of common stock (in shares)			(4,600,000)
Repurchases of common stock	(735.3)				(735.3)
Dividends paid	(112.3)			0.6	(112.9)
Incentive compensation plan stock withheld for taxes	(27.8)				(27.8)
Unrealized gain from cash flow hedge, net of tax	0.0
Reclassification of cash flow hedge loss to net income	1.0						1.0
Foreign currency translation	11.6						11.6
Ending balance (in shares) at Jun. 30, 2021			138,300,000
Ending balance at Jun. 30, 2021	1,048.8		$ 1.4	3,294.1	(2,163.5)		(83.2)
Beginning balance (in shares) at Mar. 31, 2021			140,400,000
Beginning balance at Mar. 31, 2021	1,170.3		$ 1.4	3,262.6	(2,004.6)		(89.1)
Shareholders' Equity (Deficit) [Roll Forward]
Net income	274.1				274.1
Equity-based compensation expense	20.6			20.6
Stock option exercises (in shares)			0
Stock option exercises	4.1			4.1
Coworker Stock Purchase Plan (in shares)			100,000
Coworker Stock Purchase Plan	6.5			6.5
Repurchases of common stock (in shares)			(2,200,000)
Repurchases of common stock	(376.9)		$ 0.0		(376.9)
Dividends paid	(55.8)			0.3	(56.1)
Unrealized gain from cash flow hedge, net of tax	0.0
Reclassification of cash flow hedge loss to net income	0.6						0.6
Foreign currency translation	5.3						5.3
Ending balance (in shares) at Jun. 30, 2021			138,300,000
Ending balance at Jun. 30, 2021	1,048.8		$ 1.4	3,294.1	(2,163.5)		(83.2)
Beginning balance (in shares) at Dec. 31, 2021			134,800,000
Beginning balance at Dec. 31, 2021	705.7		$ 1.3	3,369.5	(2,570.7)		(94.4)
Shareholders' Equity (Deficit) [Roll Forward]
Net income	529.5				529.5
Equity-based compensation expense	44.6			44.6
Stock option exercises (in shares)			300,000
Stock option exercises	15.1		$ 0.1	15.0
Coworker Stock Purchase Plan (in shares)			100,000
Coworker Stock Purchase Plan	11.8			11.8
Dividends paid	(135.0)			0.9	(135.9)
Incentive compensation plan stock withheld for taxes	(20.6)				(20.6)
Unrealized gain from cash flow hedge, net of tax	1.4						1.4
Reclassification of cash flow hedge loss to net income	1.6						1.6
Foreign currency translation	(47.9)						(47.9)
Ending balance (in shares) at Jun. 30, 2022			135,200,000
Ending balance at Jun. 30, 2022	1,106.2		$ 1.4	3,441.8	(2,197.7)		(139.3)
Beginning balance (in shares) at Mar. 31, 2022			135,100,000
Beginning balance at Mar. 31, 2022	893.1		$ 1.4	3,403.7	(2,408.9)		(103.1)
Shareholders' Equity (Deficit) [Roll Forward]
Net income	279.3				279.3
Equity-based compensation expense	23.5			23.5
Stock option exercises (in shares)			0
Stock option exercises	6.8			6.8
Coworker Stock Purchase Plan (in shares)			100,000
Coworker Stock Purchase Plan	7.4			7.4
Dividends paid	(67.5)			0.4	(67.9)
Incentive compensation plan stock withheld for taxes	(0.2)				(0.2)
Unrealized gain from cash flow hedge, net of tax	1.0						1.0
Reclassification of cash flow hedge loss to net income	0.8						0.8
Foreign currency translation	(38.0)						(38.0)
Ending balance (in shares) at Jun. 30, 2022			135,200,000
Ending balance at Jun. 30, 2022	$ 1,106.2		$ 1.4	$ 3,441.8	$ (2,197.7)		$ (139.3)