Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 26,623	$ 22,351
Other comprehensive income (loss):
Foreign currency translation adjustments	2,517	1,657
Total other comprehensive income	2,517	1,657
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	29,140	24,008
Net Income (Loss) Attributable to Noncontrolling Interest	196	192
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 28,944	$ 23,816