CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net earnings	$ 73,151	$ 63,529	$ 183,909	$ 157,513
Other comprehensive income (loss), net of tax:
Fair value adjustment on interest rate swap contracts	0	0	0	187
Ralized gain reclassified to earnings	0	(494)	0	(494)
Unealized gain on available-for-sale investments	0	(3)	0	(4)
Foreign currency translation adjustments	5,308	19,993	(26,296)	55,788
Total other comprehensive income	5,308	19,496	(26,296)	55,477
Comprehensive income	$ 78,459	$ 83,025	$ 157,613	$ 212,990

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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