CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net earnings	$ 63,529	$ 58,633	$ 157,513	$ 105,126
Other comprehensive income (loss), net of tax:
Fair value adjustment on interest rate swap contracts	0	292	187	(573)
Ralized gain reclassified to earnings	(494)	0	(494)	0
Unealized gain on available-for-sale investments	(3)	0	(4)	0
Foreign currency translation adjustments	19,993	(7,724)	55,788	(9,250)
Total other comprehensive income (loss)	19,496	(7,432)	55,477	(9,823)
Comprehensive income	$ 83,025	$ 51,201	$ 212,990	$ 95,303

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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