CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (72)	$ 1,172	$ 809	$ 5,476
Other comprehensive income, before tax:
Foreign currency translation adjustments	157	(116)	587	78
Unrealized gains on available-for-sale securities:
Unrealized gains (losses)	0	(36)	31	32
Reclassification adjustments	0	0	0	0
Total unrealized gains (losses) on available-for-sale securities	0	(36)	31	32
Unrealized gains on foreign exchange forward contracts:
Unrealized gains	0	0	0	53
Reclassification adjustments for losses included in net income (loss)	0	0	0	36
Total unrealized gains on foreign exchange forward contracts	0	0	0	89
Other comprehensive income (loss), before tax	157	(152)	618	199
Income tax provision related to items of other comprehensive income (loss)	(35)	0	(184)	0
Other comprehensive income (loss), net of tax	122	(152)	434	199
Total comprehensive income	$ 50	$ 1,020	$ 1,243	$ 5,675