Shareholder's Equity - Change in Shareholders' Equity (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)		75,300,000			75,300,000
Beginning balance	$ 2,776.2	$ 2,684.9	$ 2,326.2	$ 2,335.4	$ 2,684.9	$ 2,335.4
Beginning balance (in shares)		1,200,000			1,200,000
Net income	155.1	$ 140.0	188.5	173.8	$ 295.1	$ 362.3
Activity related to stock-based compensation	$ 18.0	11.0	$ 15.1	0.1
Share purchased under share repurchase program (in shares)	492,710		86,667		676,070	476,667
Shares purchased under share repurchase program	$ (173.4)	(60.1)	$ (28.6)	(147.1)	$ (233.5)	$ (175.7)
Dividends declared	(14.1)	(14.2)	(13.3)	(13.2)
Other comprehensive (loss) income, net of tax	$ (15.1)	14.6	(63.5)	(22.8)	$ (0.5)	(86.3)
Ending balance (in shares)	75,300,000				75,300,000
Ending balance	$ 2,746.7	$ 2,776.2	$ 2,424.4	$ 2,326.2	$ 2,746.7	$ 2,424.4
Ending balance (in shares)	1,400,000				1,400,000
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	75,300,000	75,300,000	75,300,000	75,300,000	75,300,000	75,300,000
Beginning balance	$ 18.8	$ 18.8	$ 18.8	$ 18.8	$ 18.8	$ 18.8
Ending balance (in shares)	75,300,000	75,300,000	75,300,000	75,300,000	75,300,000	75,300,000
Ending balance	$ 18.8	$ 18.8	$ 18.8	$ 18.8	$ 18.8	$ 18.8
Capital in Excess of Par Value
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	181.4	232.2	219.9	249.0	232.2	249.0
Activity related to stock-based compensation	(23.2)	(50.8)	5.4	(29.1)
Ending balance	158.2	181.4	225.3	219.9	158.2	225.3
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ (369.2)	$ (370.9)	$ (347.4)	$ (229.5)	$ (370.9)	$ (229.5)
Beginning balance (in shares)	1,100,000	1,200,000	1,200,000	1,100,000	1,200,000	1,100,000
Activity related to stock-based compensation	$ 41.2	$ 61.8	$ 9.7	$ 29.2
Activity related to stock -based compensation (in shares)	(200,000)	(300,000)	0	(300,000)
Share purchased under share repurchase program (in shares)	500,000	200,000	100,000	400,000
Shares purchased under share repurchase program	$ (173.4)	$ (60.1)	$ (28.6)	$ (147.1)
Ending balance	$ (501.4)	$ (369.2)	$ (366.3)	$ (347.4)	$ (501.4)	$ (366.3)
Ending balance (in shares)	1,400,000	1,100,000	1,300,000	1,200,000	1,400,000	1,300,000
Retained earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 3,113.6	$ 2,987.8	$ 2,617.3	$ 2,456.7	$ 2,987.8	$ 2,456.7
Net income	155.1	140.0	188.5	173.8
Dividends declared	(14.1)	(14.2)	(13.3)	(13.2)
Ending balance	3,254.6	3,113.6	2,792.5	2,617.3	3,254.6	2,792.5
Accumulated other comprehensive loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(168.4)	(183.0)	(182.4)	(159.6)	(183.0)	(159.6)
Other comprehensive (loss) income, net of tax	(15.1)	14.6	(63.5)	(22.8)
Ending balance	$ (183.5)	$ (168.4)	$ (245.9)	$ (182.4)	$ (183.5)	$ (245.9)