Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (1,753)	$ (6,854)	$ (1,969)	$ (9,360)
Other comprehensive income (loss):
Foreign currency translation adjustments	(594)	380	(178)	496
Unrealized gains (losses) from marketable securities, net of tax	(2)	0	(3)	1
Total other comprehensive income (loss)	(596)	380	(181)	497
Comprehensive loss	$ (2,349)	$ (6,474)	$ (2,150)	$ (8,863)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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