Consolidated Statements of Stockholders' Deficit - USD ($) $ in Millions	Total	Common Stock Issued	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock at Cost
Beginning balance at Dec. 31, 2023	$ 285.3	$ 0.9	$ 1,184.6	$ 3,506.2	$ (56.9)	$ (4,349.5)
Beginning balance (in shares) at Dec. 31, 2023						51,600,000
Net income	609.2			609.2
Dividends	(121.4)			(121.4)
Foreign currency translation adjustments	(19.4)				(19.4)
Share of equity method investments other comprehensive income					0.2
Pension and post-retirement liability changes, net of tax	(0.4)				(0.4)
Stock-based compensation expense	20.1		20.1
Change in cash flow hedges, net of tax	6.2				6.2
Treasury shares reissued for common stock	3.2		0.2			$ 3.0
Treasury shares reissued for common stock (in shares)						(100,000)
Treasury stock purchases	(28.6)					$ (28.6)
Ending balance at Sep. 30, 2024	754.0	0.9	1,204.9	3,994.0	(70.7)	$ (4,375.1)
Ending balance (in shares) at Sep. 30, 2024						51,500,000
Beginning balance at Jun. 30, 2024	577.4	0.9	1,197.9	3,796.0	(60.8)	$ (4,356.6)
Beginning balance (in shares) at Jun. 30, 2024						51,500,000
Net income	239.0			239.0
Dividends	(41.0)			(41.0)
Foreign currency translation adjustments	(9.9)				(9.9)
Share of equity method investments other comprehensive income	0.2				0.2
Pension and post-retirement liability changes, net of tax	0.2				0.2
Stock-based compensation expense	6.8		6.8
Treasury shares reissued for common stock	1.1		0.2			$ 0.9
Treasury shares reissued for common stock (in shares)						0
Treasury stock purchases	(19.4)					$ (19.4)
Ending balance at Sep. 30, 2024	754.0	0.9	1,204.9	3,994.0	(70.7)	$ (4,375.1)
Ending balance (in shares) at Sep. 30, 2024						51,500,000
Beginning balance at Dec. 31, 2024	$ 850.2	0.9	1,213.3	4,150.8	(93.7)	$ (4,421.1)
Beginning balance (in shares) at Dec. 31, 2024	51,573,986					51,600,000
Net income	$ 643.7			643.7
Dividends	(132.0)			(132.0)
Foreign currency translation adjustments	21.1				21.1
Share of equity method investments other comprehensive income	(0.2)				(0.2)
Stock-based compensation expense	20.8		20.8
Purchase of common stock under Employee Stock Purchase Program	0.4		0.4
Change in cash flow hedges, net of tax	10.8				10.8
Treasury shares reissued for common stock	3.9		1.6			$ 2.3
Treasury shares reissued for common stock (in shares)						(100,000)
Treasury stock purchases (in shares)						600,000
Treasury stock purchases	(348.6)					$ (348.6)
Ending balance at Sep. 30, 2025	$ 1,070.1	0.9	1,236.1	4,662.5	(62.0)	$ (4,767.4)
Ending balance (in shares) at Sep. 30, 2025	52,096,681					52,100,000
Beginning balance at Jun. 30, 2025	$ 900.5	0.9	1,228.3	4,462.1	(61.4)	$ (4,729.4)
Beginning balance (in shares) at Jun. 30, 2025						52,000,000.0
Net income	245.8			245.8
Dividends	(45.4)			(45.4)
Foreign currency translation adjustments	1.0				1.0
Share of equity method investments other comprehensive income	(0.2)				(0.2)
Stock-based compensation expense	6.3		6.3
Purchase of common stock under Employee Stock Purchase Program	0.4		0.4
Change in cash flow hedges, net of tax	(1.4)				(1.4)
Treasury shares reissued for common stock	1.3		1.1			$ 0.2
Treasury shares reissued for common stock (in shares)						0
Treasury stock purchases (in shares)						100,000
Treasury stock purchases	(38.2)					$ (38.2)
Ending balance at Sep. 30, 2025	$ 1,070.1	$ 0.9	$ 1,236.1	$ 4,662.5	$ (62.0)	$ (4,767.4)
Ending balance (in shares) at Sep. 30, 2025	52,096,681					52,100,000