CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) shares in Millions, $ in Millions	Common Stock [Member]	Capital in Excess of Par Value [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]		Treasury Stock [Member]	Total
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative-effect adjustment upon adoption of new accounting standard | ASU 2017-12 [Member]			$ (0.3)	$ 0.3	[1]
Cumulative-effect adjustment upon adoption of new accounting standard | ASU 2018-02 [Member]			0.0	0.0
Balance at beginning of period at Dec. 31, 2017	$ 2.0	$ 2,275.4	(577.8)	(199.8)		$ (23.0)
Balance at beginning of period (in shares) at Dec. 31, 2017	198.4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Purchases of treasury stock						(6.2)
Issuance of common stock for stock-based compensation plans	$ 0.0	3.3
Issuance of common stock for stock-based compensation plans (in shares)	1.0
Issuance of treasury stock for stock-based compensation plans		(1.6)				1.6
Stock-based compensation		5.2
Net income			42.4				$ 42.4
Foreign currency translation adjustments, net				34.4			34.4
Unrecognized gains on cash flow hedges, net				11.4			11.4
Pension and other postretirement prior service cost and gain or loss, net				0.4			0.4
Balance at end of period at Mar. 31, 2018	$ 2.0	2,282.3	(535.7)	(153.3)		(27.6)	1,567.7
Balance at end of period (in shares) at Mar. 31, 2018	199.4
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative-effect adjustment upon adoption of new accounting standard | ASU 2017-12 [Member]			0.0	0.0
Cumulative-effect adjustment upon adoption of new accounting standard | ASU 2018-02 [Member]			8.2	(8.2)	[1]
Balance at beginning of period at Dec. 31, 2018	$ 2.0	2,282.7	(308.7)	(247.0)		(53.0)	1,676.0
Balance at beginning of period (in shares) at Dec. 31, 2018	201.1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Purchases of treasury stock						(8.5)
Issuance of common stock for stock-based compensation plans	$ 0.0	12.9
Issuance of common stock for stock-based compensation plans (in shares)	2.2
Issuance of treasury stock for stock-based compensation plans		(9.2)				14.5
Stock-based compensation		2.9
Net income			47.1				47.1
Foreign currency translation adjustments, net				(0.1)			(0.1)
Unrecognized gains on cash flow hedges, net				1.9			1.9
Pension and other postretirement prior service cost and gain or loss, net				0.2			0.2
Balance at end of period at Mar. 31, 2019	$ 2.0	$ 2,289.3	$ (253.4)	$ (253.2)		$ (47.0)	$ 1,737.7
Balance at end of period (in shares) at Mar. 31, 2019	203.3

[1] All amounts are net of tax. Amounts in parentheses indicate debits.