Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net earnings	$ 116,439	$ 118,329	$ 213,486	$ 225,661
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments, net of tax of $5,612 and $2,363 for the three months ended June 30, 2016 and 2015 and $424 and $8,197 for the six months ended June 30, 2016 and 2015	(10,297)	4,216	(717)	(15,389)
Other comprehensive (loss) income	(10,297)	4,216	(717)	(15,389)
Comprehensive income	106,142	122,545	212,769	210,272
Less comprehensive income attributable to the noncontrolling interest	330	472	907	769
Comprehensive income attributable to shareholders	$ 105,812	$ 122,073	$ 211,862	$ 209,503