STATEMENT OF CHANGES IN EQUITY AND ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Statement of Changes in Equity (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Dec. 31, 2016
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			$ 1,190.8	$ 1,094.0
Effect of accounting change on prior years					$ (2.3)	$ 1.2
Adjusted beginning balance					1,188.5	1,095.2
Net earnings	$ 90.0	$ 83.5	253.0	257.2
Net earnings	90.0	82.6	253.0	256.3
(Earnings) loss attributable to noncontrolling interest, net of tax	0.0	0.0	(0.1)	0.0
Dividends declared			(146.2)	(140.2)
Dividends paid to noncontrolling interest			(0.2)
Treasury stock purchased			(113.2)	(161.0)
Treasury stock issued			14.2	28.0
Foreign currency translation adjustments			(50.0)	69.9
Cash flow hedges, net of tax	0.6	0.8	(0.7)	5.4
Defined benefit pension plans, net of tax	0.4	0.4	1.5	1.5
Stock-based compensation transactions, net of tax			19.1	20.3
Purchase of remaining interest in noncontrolling interest, net of acquisitions				(2.6)
Ending balance	1,166.0	1,172.8	1,166.0	1,172.8
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			2,511.3	2,410.5
Effect of accounting change on prior years					(2.3)	1.2
Adjusted beginning balance					2,509.0	2,411.7
Net earnings			253.0
Net earnings				256.3
(Earnings) loss attributable to noncontrolling interest, net of tax			(0.1)
Dividends declared			(150.2)	(144.1)
Ending balance	2,611.7	2,523.9	2,611.7	2,523.9
Common Stock & Additional Contributed Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			516.7	508.2
Adjusted beginning balance					516.7	508.2
Dividends declared			4.0	3.9
Treasury stock issued			(16.1)	(15.8)
Stock-based compensation transactions, net of tax			19.1	20.3
Purchase of remaining interest in noncontrolling interest, net of acquisitions				(0.7)
Ending balance	523.7	515.9	523.7	515.9
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			(1,828.3)	(1,713.5)
Adjusted beginning balance					(1,828.3)	(1,713.5)
Treasury stock purchased			(113.2)	(161.0)
Treasury stock issued			30.3	43.8
Ending balance	(1,911.2)	(1,830.7)	(1,911.2)	(1,830.7)
Noncontrolling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			0.6	2.4
Adjusted beginning balance					0.6	2.4
(Earnings) loss attributable to noncontrolling interest, net of tax			0.1
Dividends paid to noncontrolling interest			(0.2)
Foreign currency translation adjustments				0.1
Purchase of remaining interest in noncontrolling interest, net of acquisitions				(1.9)
Ending balance	0.5	0.6	0.5	0.6
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance			(9.5)	(113.6)
Adjusted beginning balance					$ (9.5)	$ (113.6)
Foreign currency translation adjustments			(50.0)	69.8
Cash flow hedges, net of tax			(0.7)	5.4
Defined benefit pension plans, net of tax			1.5	1.5
Ending balance	$ (58.7)	$ (36.9)	$ (58.7)	$ (36.9)