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)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	988.6				988.6
Equity-based compensation expense	72.6			72.6
Stock option exercises (in shares)			1,500,000
Stock option exercises	69.9			69.9
Coworker Stock Purchase Plan (in shares)			100,000
Coworker Stock Purchase Plan	20.6			20.6
Repurchases of common stock (in shares)			(8,700,000)
Repurchases of common stock	(1,500.4)		$ (0.1)		(1,500.3)
Dividend payments	(234.8)			1.5	(236.3)
Incentive compensation plan stock withheld for taxes	(28.5)				(28.5)
Unrealized loss on cash flow hedge	0.0
Reclassification of cash flow hedge to net income	2.5						2.5
Foreign currency translation	(1.1)						(1.1)
Ending balance (in shares) at Dec. 31, 2021			134,800,000
Ending balance at Dec. 31, 2021	705.7		$ 1.3	3,369.5	(2,570.7)		(94.4)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,114.5				1,114.5
Equity-based compensation expense	91.1			91.1
Stock option exercises (in shares)			500,000
Stock option exercises	30.2		$ 0.1	30.1
Coworker Stock Purchase Plan (in shares)			200,000
Coworker Stock Purchase Plan	25.5			25.5
Dividend payments	(282.6)			1.9	(284.5)
Incentive compensation plan stock withheld for taxes	(23.1)				(23.1)
Unrealized loss on cash flow hedge	(0.1)						(0.1)
Reclassification of cash flow hedge to net income	3.6						3.6
Foreign currency translation	(61.5)						(61.5)
Ending balance (in shares) at Dec. 31, 2022			135,500,000
Ending balance at Dec. 31, 2022	1,603.3		$ 1.4	3,518.1	(1,763.8)		(152.4)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,104.3				1,104.3
Equity-based compensation expense	$ 93.7			93.7
Stock option exercises (in shares)	714,538		1,000,000.0
Stock option exercises	$ 49.3			49.3
Coworker Stock Purchase Plan (in shares)			200,000
Coworker Stock Purchase Plan	28.2			28.2
Repurchases of common stock (in shares)			(2,600,000)
Repurchases of common stock	(500.0)		$ (0.1)		(499.9)
Dividend payments	(321.5)			2.0	(323.5)
Incentive compensation plan stock withheld for taxes	(40.0)				(40.0)
Unrealized loss on cash flow hedge	(1.9)						(1.9)
Reclassification of cash flow hedge to net income	0.0
Foreign currency translation	27.1				(2.6)		29.7
Ending balance (in shares) at Dec. 31, 2023			134,100,000
Ending balance at Dec. 31, 2023	$ 2,042.5		$ 1.3	$ 3,691.3	$ (1,525.5)		$ (124.6)