Unaudited Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Net loss	$ (5,035)	$ (6,493)	$ (15,914)	$ (16,843)
Other comprehensive income (loss):
Unrealized losses on short term investments	(10)		(10)
Unrealized gains (losses) on derivative instruments	493	(845)	2,617	379
Total other comprehensive income (loss)	483	(845)	2,607	379
Comprehensive loss	$ (4,552)	$ (7,338)	$ (13,307)	$ (16,464)

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

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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