Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (259)	$ (520)	$ (250)	$ (3,762)
Other comprehensive income (loss), net of tax
Reclassification of losses on foreign currency contracts to net income	10		28
Unrealized loss on foreign currency contracts	(56)		(127)
Other comprehensive loss	(46)		(99)
Comprehensive loss	$ (305)	$ (520)	$ (349)	$ (3,762)

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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Amount after tax of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss).

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