Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating Activities
Net loss	$ (70,275)	$ (5,152)	$ (37,110)
Adjustments to reconcile net loss to net cash used in operating activities:
Accretion of convertible notes			7,901
Non-cash interest			15
Depreciation and amortization	5,535	5,148	2,528
Amortization of debt discount	28
Amortization of premium on investment securities	288
Loss (gain) on sales of property and equipment	(2)	11
Impairment of assets	1,557
Stock based compensation	7,326	5,157	1,657
(Gain)/loss from changes in fair value of warrants	1,481	1,664	(52)
(Gain)/loss from change in fair value of long term debt	(964)	(118)	2,166
Provision for doubtful accounts	529	349	527
Loss on debt extinguishment	7,313
Changes in operating assets and liabilities
Accounts receivable	(450)	341	(5,848)
Inventory	2,929	(890)	(9,054)
Prepaid expenses and other current assets	(3,797)	(137)	(820)
Restricted cash	(273)
Other assets	(1,041)	(24)	(63)
Accounts payable	1,354	(2,430)	6,792
Income taxes payable		(15)
Accrued compensation	2,572	2,994	1,658
Other accrued liabilities	8,026	4,450	4,702
Deferred revenue	32	(858)	869
Net cash (used in) provided by operating activities	(37,832)	10,490	(24,132)
Investing Activities
Purchases of investments	(203,290)
Proceeds from sale of property and equipment	463	15
Purchases of property and equipment, net	(7,852)	(9,957)	(8,245)
Net cash (used in) investing activities	(210,679)	(9,942)	(8,245)
Financing Activities
Proceeds from issuance of common stock, net of issuance costs	180,001	170	259
Proceeds from exercise of stock options	1,258
Bridge loan			2,000
Proceeds from issuance of preferred stock, net		55,413	33,019
Proceeds from senior secured term loan			20,000
Costs paid for loan	(6)		(479)
Proceeds from short-term financing	42,000
Proceeds from equipment financing		5,105	3,700
Repayments of equipment financing	(5,850)	(2,480)	(475)
Repayments of secured financings	(20,000)
Proceeds from collection of officer receivable	192
Payment to lender for debt extinguishment	(7,313)
Change in restricted cash		(415)	(881)
Deferred offering costs		(1,661)	(17)
Net cash provided by financing activities	190,282	56,132	57,126
Net (decrease) increase in cash	(58,229)	56,680	24,749
Cash at beginning of period	87,176	30,496	5,747
Cash at end of period	28,947	87,176	30,496
Supplemental disclosure of cash flow information:
Cash paid for interest	2,060	2,063	920
Purchases of property and equipment through accounts payable and accruals	765	$ 3,223	2,942
Non cash property and equipment purchase	2
Conversion of convertible preferred stock to common stock	$ 240,585
C and D
Supplemental disclosure of cash flow information:
Conversion of Debt			139,664
Bridge loan
Supplemental disclosure of cash flow information:
Conversion of Debt			$ 2,002