Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Operating Activities
Net loss	$ (29,685)	$ (10,130)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	2,974	2,308
(Gain) on sales of property and equipment	(5)
Share based compensation	2,740	3,028
Loss from changes in fair value of warrants	3,925	452
(Gain)/loss from change in fair value of long term debt	2,122	(534)
Provision for doubtful accounts	119	315
Increase (Decrease) in Operating Capital [Abstract]
Accounts receivable	549	(2,807)
Inventory	(3,091)	(106)
Prepaid expenses and other current assets	(2,223)	(335)
Restricted cash	(262)
Other assets	(337)	(7)
Accounts payable	2,678	401
Accrued compensation	1,031	614
Other accrued liabilities	3,683	1,284
Deferred revenue	(78)	36
Net cash used in operating activities	(15,860)	(5,481)
Investing Activities
Purchases of property and equipment, net	(6,037)	(5,871)
Net cash used in investing activities	(6,037)	(5,871)
Financing Activities
Proceeds from issuance of common stock, net	315	74
Costs paid for issuance of preferred stock, net	(27)
Costs paid for senior secured term loan	(6)
Proceeds from equipment financing		1,325
Repayments of equipment financing	(1,170)	(1,141)
Proceeds from collection of officer receivable	192
Change in restricted cash		(319)
Deferred offering costs	(2,340)	(1,413)
Net cash provided by financing activities	(3,036)	(1,474)
Net decrease in cash	(24,933)	(12,826)
Cash at beginning of period	87,176	30,496
Cash at end of period	62,243	17,670
Supplemental Cash Flow Information [Abstract]
Cash paid for interest	1,514	1,051
Purchases of property and equipment through accounts payable and accruals	627	$ 678
Non cash property and equipment purchase	$ 5