Condensed Consolidated Statements of Comprehensive Income (Loss) - 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 income (loss)	$ (1,581)	$ 12,294	$ (10,801)	$ 3,134
Other comprehensive income (loss):
Foreign currency translation adjustments	(145)	(42)	(417)	85
Comprehensive income (loss)	$ (1,726)	$ 12,252	$ (11,218)	$ 3,219