Condensed Consolidated Statements of Changes in Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Treasury Stock [Member]
Beginning balance at Dec. 31, 2018	$ 4,580.0	$ 2.5	$ 4,091.4	$ 847.1	$ (343.0)	$ (18.0)
Beginning balance, shares at Dec. 31, 2018		252.4
Net income	80.8			80.8
Foreign exchange translation adjustment	41.8				41.8
Stock-based compensation expense	20.4		20.4
Exercise of options, net of withholding taxes	35.6		35.6
Exercise of options, net of withholding taxes, shares		2.0
Cash dividends declared	(25.2)			(25.2)
Other	0.1			0.1
Ending balance at Mar. 31, 2019	4,733.5	$ 2.5	4,147.4	902.8	(301.2)	(18.0)
Ending balance, shares at Mar. 31, 2019		254.4
Beginning balance at Dec. 31, 2019	$ 5,116.1	$ 2.6	4,266.9	1,177.9	(253.0)	(78.3)
Beginning balance, shares at Dec. 31, 2019	257.6	257.6
Net income	$ 99.2			99.2
Foreign exchange translation adjustment	(150.7)				(150.7)
Net change in interest rate swaps	(2.4)				(2.4)
Stock-based compensation expense	22.5		22.5
Exercise of options, net of withholding taxes	34.8		34.8
Exercise of options, net of withholding taxes, shares		1.4
Cash dividends declared	(31.9)		0.1	(32.0)
Ending balance at Mar. 31, 2020	$ 5,087.6	$ 2.6	$ 4,324.3	$ 1,245.1	$ (406.1)	$ (78.3)
Ending balance, shares at Mar. 31, 2020	259.0	259.0