Consolidated Statement Of Changes In Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Additional Contributed Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Noncontrolling Interest
Balance, beginning of period at Dec. 31, 2015	$ 1,097.7	$ 2.0	$ 529.5	$ 2,209.2	$ (91.1)	$ (1,564.0)	$ 12.1
Balance, beginning of period, shares at Dec. 31, 2015		198.8				(63.2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings	386.2			386.2
(Earnings) attributable to noncontrolling interest, net of tax	(0.4)			(0.4)			0.4
Dividends declared	(179.4)		5.1	(184.5)
Dividends paid to noncontrolling interest	(1.6)						(1.6)
Treasury stock purchased	(210.9)					$ (210.9)
Treasury stock purchased, shares						(4.5)
Treasury stock issued	36.0		(25.4)			$ 61.4
Treasury stock issued, shares						2.4
Other comprehensive income, net of tax (See Note Q)	(23.6)				(23.5)		(0.1)
Stock-based compensation, net of tax	24.9		24.9
Purchase of remaining interest in noncontrolling interest	(35.3)		(27.9)		1.0		(8.4)
Balance, end of period at Dec. 31, 2016	1,094.0	$ 2.0	506.2	2,410.5	(113.6)	$ (1,713.5)	2.4
Balance, end of period, shares at Dec. 31, 2016		198.8				(65.3)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adjusted beginning balance	1,095.1	$ 2.0	506.2	2,411.6	(113.6)	$ (1,713.5)	2.4
Net earnings	292.7			292.7
(Earnings) attributable to noncontrolling interest, net of tax	(0.1)			(0.1)			0.1
Dividends declared	(187.7)		5.2	(192.9)
Treasury stock purchased	(162.1)					$ (162.1)
Treasury stock purchased, shares						(3.3)
Treasury stock issued	31.2		(16.1)			$ 47.3
Treasury stock issued, shares						1.7
Other comprehensive income, net of tax (See Note Q)	103.7				103.7
Stock-based compensation, net of tax	20.0		20.0
Purchase of remaining interest in noncontrolling interest	(2.6)		(0.6)		0.4		(2.4)
Acquisition of noncontrolling interest	0.5						0.5
Balance, end of period at Dec. 31, 2017	1,190.8	$ 2.0	514.7	2,511.3	(9.5)	$ (1,828.3)	0.6
Balance, end of period, shares at Dec. 31, 2017		198.8				(66.9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adjusted beginning balance	1,188.5	$ 2.0	514.7	2,509.0	(9.5)	$ (1,828.3)	0.6
Net earnings	306.1			306.1
(Earnings) attributable to noncontrolling interest, net of tax	(0.2)			(0.2)			0.2
Dividends declared	(195.8)		5.3	(201.1)
Dividends paid to noncontrolling interest	(0.2)						(0.2)
Treasury stock purchased	(113.6)					$ (113.6)
Treasury stock purchased, shares						(2.6)
Treasury stock issued	17.0		(16.6)			$ 33.6
Treasury stock issued, shares						1.2
Other comprehensive income, net of tax (See Note Q)	(68.1)				(68.1)
Stock-based compensation, net of tax	23.7		23.7
Balance, end of period at Dec. 31, 2018	$ 1,157.6	$ 2.0	$ 527.1	$ 2,613.8	$ (77.6)	$ (1,908.3)	$ 0.6
Balance, end of period, shares at Dec. 31, 2018		198.8				(68.3)