Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 4,038	$ 1,228	$ 6,163	$ 9
Other comprehensive income (loss), net of tax
Unrealized income (loss) on foreign currency contracts	166	(22)	108	(53)
Comprehensive income (loss)	$ 4,204	$ 1,206	$ 6,271	$ (44)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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