Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 8,490	$ 10,205	$ 15,336	$ 18,076
Other comprehensive income (loss):
Foreign currency translation adjustment	6	(11)	89	23
Tax benefit (provision)		2	(16)	(4)
Comprehensive income	$ 8,496	$ 10,196	$ 15,409	$ 18,095