Condensed Consolidated Statements of Stockholders' Equity (Deficit) - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Common Stock in Treasury	Accumulated Other Comprehensive Loss, Net of Taxes
Balance at beginning of period at Dec. 31, 2018	$ (348.6)	$ 23.2	$ 2,049.6	$ 1,835.5	$ (3,336.5)	$ (920.4)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Effect of share-based incentive compensation	14.6		14.6
Stock issued for profit sharing contribution paid in stock	21.9		0.5		21.4
Repurchases of common stock	(67.3)				(67.3)
Recognition of pension items, net of taxes	2.6					2.6
Foreign currency translation adjustments	(25.7)					(25.7)
Unrealized (loss) gain on derivative instruments, net of taxes	14.7					14.7
Net earnings	158.7			158.7
Dividends on common stock	(75.0)			(75.0)
Balance at end of period at Sep. 30, 2019	(304.1)	23.2	2,064.7	1,919.2	(3,382.4)	(928.8)
Balance at beginning of period at Jun. 30, 2019	(341.2)	23.2	2,053.0	1,876.4	(3,382.4)	(911.4)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Effect of share-based incentive compensation	11.7		11.7
Recognition of pension items, net of taxes	0.9					0.9
Foreign currency translation adjustments	(32.0)					(32.0)
Unrealized (loss) gain on derivative instruments, net of taxes	13.7					13.7
Net earnings	68.0			68.0
Dividends on common stock	(25.2)			(25.2)
Balance at end of period at Sep. 30, 2019	(304.1)	23.2	2,064.7	1,919.2	(3,382.4)	(928.8)
Balance at beginning of period at Dec. 31, 2019	(196.2)	23.2	2,073.5	1,998.5	(3,382.4)	(909.0)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Effect of share-based incentive compensation	20.9		20.9
Stock issued for profit sharing contribution paid in stock	24.4		(11.7)		36.1
Repurchases of common stock	(20.0)				(20.0)
Recognition of pension items, net of taxes	3.9					3.9
Foreign currency translation adjustments	(77.5)					(77.5)
Unrealized (loss) gain on derivative instruments, net of taxes	(16.3)					(16.3)
Net earnings	360.7			360.7
Dividends on common stock	(75.4)			(75.4)
Balance at end of period at Sep. 30, 2020	24.5	23.2	2,082.7	2,283.8	(3,366.3)	(998.9)
Balance at beginning of period at Jun. 30, 2020	(70.1)	23.2	2,070.9	2,175.1	(3,346.3)	(993.0)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Effect of share-based incentive compensation	11.8		11.8
Repurchases of common stock	(20.0)				(20.0)
Recognition of pension items, net of taxes	1.8					1.8
Foreign currency translation adjustments	9.6					9.6
Unrealized (loss) gain on derivative instruments, net of taxes	(17.3)					(17.3)
Net earnings	134.0			134.0
Dividends on common stock	(25.3)			(25.3)
Balance at end of period at Sep. 30, 2020	$ 24.5	$ 23.2	$ 2,082.7	$ 2,283.8	$ (3,366.3)	$ (998.9)