Quarterly Results of Operations (unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 44,003	$ 45,986	$ 48,556	$ 42,612	$ 47,463	$ 52,122	$ 50,974	$ 42,366	$ 181,157	$ 192,925	$ 153,612
Gross Profit	31,356	29,107	32,224	28,642	29,461	36,931	29,459	27,941	59,828	69,133	51,821
Operating expenses	40,261	38,454	40,130	44,304	51,669	48,165	52,687	66,345	163,149	218,866	154,704
Net loss	$ (14,521)	$ (14,273)	$ (16,292)	$ (21,314)	$ (24,924)	$ (15,245)	$ (66,837)	$ (47,671)	$ (66,400)	$ (154,677)	$ (50,424)
Basic and diluted net loss per share (in USD per share)	$ (0.17)	$ (0.17)	$ (0.20)	$ (0.26)	$ (0.30)	$ (0.18)	$ (0.81)	$ (0.62)	$ (0.80)	$ (1.91)	$ (0.75)

Total costs related to goods produced and sold during the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a))
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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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