Condensed 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	$ 43,720	$ 25,341	$ 134,467	$ 114,976
Other Comprehensive Income (Loss):
Foreign Currency Translation Adjustment	297	782	(715)	1,431
Total Other Comprehensive Income (Loss)	297	782	(715)	1,431
Comprehensive Income	$ 44,017	$ 26,123	$ 133,752	$ 116,407