CONSOLIDATED STATEMENT OF EQUITY - USD ($) $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Common stock	Capital in excess of par value	Treasury stock	Retained earnings	Retained earnings Cumulative Effect, Period of Adoption, Adjustment	Accumulated other comprehensive loss
Accounting Standards Update [Extensible List]	Accounting Standards Update 2016-13 [Member]
Balance (in shares) at Dec. 31, 2018			75,300,000		1,200,000
Beginning balance at Dec. 31, 2018	$ 1,396.3		$ 18.8	$ 282.0	$ (103.7)	$ 1,353.4		$ (154.2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	241.7					241.7
Activity related to stock-based compensation (in shares)					(800,000)
Activity related to stock-based compensation	54.5			(11.1)	$ 65.6
Shares purchased under share repurchase program (in shares)					800,000
Shares purchased under share repurchase program	(83.1)				$ (83.1)
Purchase of investment in affiliated companies	4.9			1.8	$ 3.1
Dividends declared	(45.7)					(45.7)
Other comprehensive income, net of tax	4.6							4.6
Balance (in shares) at Dec. 31, 2019			75,300,000		1,200,000
Ending balance at Dec. 31, 2019	1,573.2	$ (0.1)	$ 18.8	272.7	$ (118.1)	1,549.4	$ (0.1)	(149.6)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	346.2					346.2
Activity related to stock-based compensation (in shares)					(700,000)
Activity related to stock-based compensation	60.5			(5.4)	$ 65.9
Shares purchased under share repurchase program (in shares)					800,000
Shares purchased under share repurchase program	(115.5)				$ (115.5)
Dividends declared	(48.8)					(48.8)
Other comprehensive income, net of tax	39.0							39.0
Balance (in shares) at Dec. 31, 2020			75,300,000		1,300,000
Ending balance at Dec. 31, 2020	1,854.5		$ 18.8	267.3	$ (167.7)	1,846.7		(110.6)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	661.8					661.8
Activity related to stock-based compensation (in shares)					(700,000)
Activity related to stock-based compensation	$ 57.0			(18.3)	$ 75.3
Shares purchased under share repurchase program (in shares)	(479,000)				500,000
Shares purchased under share repurchase program	$ (137.1)				$ (137.1)
Dividends declared	(51.8)					(51.8)
Other comprehensive income, net of tax	(49.0)							(49.0)
Balance (in shares) at Dec. 31, 2021			75,300,000		1,100,000
Ending balance at Dec. 31, 2021	$ 2,335.4		$ 18.8	$ 249.0	$ (229.5)	$ 2,456.7		$ (159.6)