Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Operating activities
Net loss	$ (11,806)	$ (16,898)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization of property and equipment	472	421
Amortization of financing costs	13	3,983
Noncash interest expense	1,571	2,601
Share-based compensation expense	1,429	561
Obsolete inventory reserve	111	0
Change in fair value of derivative liabilities	(198)	593
Gain on sale of property and equipment	(66)	0
Accrued restructuring cost	0	1,331
Changes in:
Accounts receivable	(157)	(328)
Other receivables	(276)	351
Inventories	998	(913)
Deferred cost of goods sold	(52)	109
Prepaid expense and other current assets	284	162
Accounts payable	507	(1,837)
Accrued expense	(950)	(777)
Deferred revenue	161	(161)
Deferred rent liability	(19)	(92)
Net cash used in operating activities	(7,978)	(10,894)
Investing activities
Proceeds from sale of property and equipment	66	0
Acquisition of property and equipment	(43)	(143)
Net cash provided by (used in) investing activities	23	(143)
Financing activities
Repayment of capital lease	0	(26)
Proceeds from issuance of private company Series AB Preferred Stock received from related party	0	5,819
Proceeds from issuance of common stock ($40,000 received from a related party), net of issuance costs	49,308	0
Costs associated with investor capital contributions	0	(162)
Payment of debt restructuring costs	(35)	0
Proceeds from exercise of warrants by a related party	0	7,026
Net cash provided by financing activities	49,273	12,657
Net increase in cash and cash equivalents	41,318	1,620
Cash and cash equivalents-beginning of period	9,866	2,789
Cash and cash equivalents-end of period	51,184	4,409
Supplemental disclosures of cash flow information
Accrued property and equipment	0	24
Accrued offering costs/acquisition related costs	516	91
Write off of debt issuance costs	107	0
Conversion of debt to Series A preferred stock	$ 27,500	$ 0