Consolidated Statements of Total Equity (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Retained Earnings	Total Shareholders' Equity	Noncontrolling Interests
Beginning Balance at Dec. 31, 2019	$ 5,353.3	$ 0.6	$ 3,418.8	$ (145.8)	$ 2,077.2	$ 5,350.8	$ 2.5
Beginning Balance (in shares) at Dec. 31, 2019		62.4
Consolidated net earnings	25.9				25.9	25.9
Other comprehensive earnings, net of tax	0.4			0.4		0.4
Dividends declared	(34.5)				(34.5)	(34.5)
Issuances of common stock for stock award plans	4.5		4.5			4.5
Shares withheld for employees' income tax obligations	(12.7)		(12.7)			(12.7)
Repurchases of common stock	(50.0)				(50.0)	(50.0)
Repurchases of common stock, Shares		(0.2)
Stock-based compensation expense	12.5		12.5			12.5
Ending Balance at Mar. 31, 2020	5,299.4	$ 0.6	3,423.1	(145.4)	2,018.6	5,296.9	2.5
Ending Balance (in shares) at Mar. 31, 2020		62.2
Beginning Balance at Dec. 31, 2020	5,893.3	$ 0.6	3,440.8	(158.4)	2,607.7	5,890.7	2.6
Beginning Balance (in shares) at Dec. 31, 2020		62.3
Consolidated net earnings	65.5				65.3	65.3	0.2
Other comprehensive earnings, net of tax	2.8			2.8		2.8
Dividends declared	(35.8)				(35.8)	(35.8)
Issuances of common stock for stock award plans	5.5		5.5			5.5
Issuances of common stock for stock award plans (in shares)		0.1
Shares withheld for employees' income tax obligations	(15.5)		(15.5)			(15.5)
Stock-based compensation expense	10.9		10.9			10.9
Ending Balance at Mar. 31, 2021	$ 5,926.7	$ 0.6	$ 3,441.7	$ (155.6)	$ 2,637.2	$ 5,923.9	$ 2.8
Ending Balance (in shares) at Mar. 31, 2021		62.4