Components of Equity (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance			$ 1,694,676	$ 1,871,608
Exercise of stock options			119,509	88,851
Issuance of shares under stock purchase plan			28,136	25,850
Shares repurchased under provisions of stock repurchase plans			(268,097)	(415,475)
Stock compensation expense			34,264	32,489
Tax (deficiency) benefit from stock plans, net			(2,533)	1,191
Net earnings	$ 107,949	$ 118,736	321,435	344,397
Other comprehensive loss	260	(21,692)	(457)	(37,081)
Dividends paid			(73,000)	(68,781)
Distributions to noncontrolling interest				(857)
Ending Balance	1,853,933	1,842,192	1,853,933	1,842,192
Shareholders' Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance			1,691,993	1,868,408
Exercise of stock options			119,509	88,851
Issuance of shares under stock purchase plan			28,136	25,850
Shares repurchased under provisions of stock repurchase plans			(268,097)	(415,475)
Stock compensation expense			34,264	32,489
Tax (deficiency) benefit from stock plans, net			(2,533)	1,191
Net earnings			320,217	342,774
Other comprehensive loss			(406)	(36,262)
Dividends paid			(73,000)	(68,781)
Ending Balance	1,850,083	1,839,045	1,850,083	1,839,045
Noncontrolling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance			2,683	3,200
Net earnings			1,218	1,623
Other comprehensive loss			(51)	(819)
Distributions to noncontrolling interest				(857)
Ending Balance	$ 3,850	$ 3,147	$ 3,850	$ 3,147