Consolidated Statements of Stockholders' (Deficit) Equity Consolidated Statements of Stockholders' (Deficit) Equity - USD ($) $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock [Member]
Treasury Stock, Shares						45,400,000
Beginning balance at Dec. 31, 2017	$ 50.1	$ 0.9	$ 1,061.5	$ 1,575.9	$ (157.4)	$ (2,430.8)
Cumulative Effect on Retained Earnings, Net of Tax	(6.2)			18.3	(24.5)
Net income	175.5			175.5
Dividends, Common Stock, Cash	(46.9)			(46.9)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	(9.6)				(9.6)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent	10.0				10.0
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	0.5				0.5
Stock-based compensation expense	13.6
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	13.6		13.6
Stock Issued During Period, Value, Treasury Stock Reissued	1.6		(6.7)			$ 8.3
Stock Issued During Period, Shares, Treasury Stock Reissued						(300,000)
Treasury Stock, Shares, Acquired						1,800,000
Treasury Stock, Value, Acquired, Cost Method	(368.8)					$ (368.8)
Ending balance at Jun. 30, 2018	(180.2)	0.9	1,068.4	1,722.8	(181.0)	$ (2,791.3)
Treasury Stock, Shares						45,900,000
Beginning balance at Mar. 31, 2018	(102.6)	0.9	1,036.7	1,609.6	(181.3)	$ (2,568.5)
Cumulative Effect on Retained Earnings, Net of Tax	1.4			1.4
Net income	137.6			137.6
Dividends, Common Stock, Cash	(25.8)			(25.8)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	(2.5)				(2.5)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent	2.1				2.1
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	0.7				0.7
Stock-based compensation expense	8.8
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	8.8		8.8
Stock Issued During Period, Value, Treasury Stock Reissued	0.8		$ 0.4			$ 0.4
Treasury Stock, Shares, Acquired			22,500,000			1,000,000.0
Treasury Stock, Value, Acquired, Cost Method	(200.7)					$ (223.2)
Ending balance at Jun. 30, 2018	$ (180.2)	0.9	$ 1,068.4	1,722.8	(181.0)	$ (2,791.3)
Treasury Stock, Shares						46,900,000
Treasury Stock, Shares	47,312,248					47,300,000
Beginning balance at Dec. 31, 2018	$ (149.6)	0.9	1,078.8	1,855.0	(188.8)	$ (2,895.5)
Cumulative Effect on Retained Earnings, Net of Tax	(0.3)			(0.3)
Net income	180.0			180.0
Dividends, Common Stock, Cash	(55.3)			(55.3)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	3.6				3.6
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent	6.0				6.0
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	49.6				49.6
Stock-based compensation expense	11.4
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	11.4		11.4
Stock Issued During Period, Value, Treasury Stock Reissued	1.6		(4.4)			$ 6.0
Stock Issued During Period, Shares, Treasury Stock Reissued						(200,000)
Treasury Stock, Shares, Acquired						1,000,000.0
Treasury Stock, Value, Acquired, Cost Method	(264.5)					$ (264.5)
Ending balance at Jun. 30, 2019	(217.5)	0.9	1,085.8	1,979.4	(129.6)	$ (3,154.0)
Treasury Stock, Shares						47,600,000
Beginning balance at Mar. 31, 2019	(204.8)	0.9	1,079.4	1,898.7	(180.2)	$ (3,003.6)
Net income	110.7			110.7
Dividends, Common Stock, Cash	(30.0)			(30.0)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	(2.6)				(2.6)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent	3.4				3.4
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	49.8				49.8
Stock-based compensation expense	6.1
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	6.1		6.1
Stock Issued During Period, Value, Treasury Stock Reissued	0.9		0.3			$ 0.6
Treasury Stock, Shares, Acquired						500,000
Treasury Stock, Value, Acquired, Cost Method	(151.0)					$ (151.0)
Ending balance at Jun. 30, 2019	$ (217.5)	$ 0.9	$ 1,085.8	$ 1,979.4	$ (129.6)	$ (3,154.0)
Treasury Stock, Shares	47,609,360					48,100,000