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	283.4			283.4
Dividends, Common Stock, Cash	(72.6)			(72.6)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	(12.7)				(12.7)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent	18.5				18.5
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	0.5				0.5
Stock-based compensation expense	21.0
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	21.0		21.0
Stock Issued During Period, Value, Treasury Stock Reissued	2.3		(7.0)			$ 9.3
Stock Issued During Period, Shares, Treasury Stock Reissued						(300,000)
Treasury Stock, Shares, Acquired						1,800,000
Treasury Stock, Value, Acquired, Cost Method	(371.1)					$ (371.1)
Ending balance at Sep. 30, 2018	(86.8)	0.9	1,075.5	1,805.0	(175.6)	$ (2,792.6)
Treasury Stock, Shares						46,900,000
Beginning balance at Jun. 30, 2018	(180.2)	0.9	1,068.4	1,722.8	(181.0)	$ (2,791.3)
Net income	108.0			108.0
Dividends, Common Stock, Cash	(25.8)			(25.8)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	(3.2)				(3.2)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent	8.6				8.6
Stock-based compensation expense	7.4
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	7.4		7.4
Stock Issued During Period, Value, Treasury Stock Reissued	0.8		$ (0.3)			$ 1.1
Treasury Stock, Shares, Acquired			0			0
Treasury Stock, Value, Acquired, Cost Method	(2.4)					$ (2.4)
Ending balance at Sep. 30, 2018	$ (86.8)	0.9	$ 1,075.5	1,805.0	(175.6)	$ (2,792.6)
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	294.7			294.7
Dividends, Common Stock, Cash	(85.0)			(85.0)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	3.3				3.3
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent	(0.3)				(0.3)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	58.6				58.6
Stock-based compensation expense	15.6
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	15.6		15.6
Stock Issued During Period, Value, Treasury Stock Reissued	2.6		(4.4)			$ 7.0
Stock Issued During Period, Shares, Treasury Stock Reissued						(200,000)
Treasury Stock, Shares, Acquired						1,500,000
Treasury Stock, Value, Acquired, Cost Method	(416.9)					$ (416.9)
Ending balance at Sep. 30, 2019	(277.3)	0.9	1,090.0	2,064.4	(127.2)	$ (3,305.4)
Treasury Stock, Shares						48,100,000
Beginning balance at Jun. 30, 2019	(217.5)	0.9	1,085.8	1,979.4	(129.6)	$ (3,154.0)
Net income	114.7			114.7
Dividends, Common Stock, Cash	(29.7)			(29.7)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax, Portion Attributable to Parent	(0.4)				(0.4)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent	(6.2)				(6.2)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	9.0				9.0
Stock-based compensation expense	4.2
APIC, Share-based Payment Arrangement, Increase for Cost Recognition	4.2		4.2
Stock Issued During Period, Value, Treasury Stock Reissued	1.0		0.0			$ 1.0
Treasury Stock, Shares, Acquired						500,000
Treasury Stock, Value, Acquired, Cost Method	(152.4)					$ (152.4)
Ending balance at Sep. 30, 2019	$ (277.3)	$ 0.9	$ 1,090.0	$ 2,064.4	$ (127.2)	$ (3,305.4)
Treasury Stock, Shares	48,642,428					48,600,000