Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities
Net loss	$ (57,246)	$ (45,722)	$ (47,889)
Adjustments to reconcile net loss to net cash used by operating activities:
Depreciation and amortization expense	2,619	2,080	1,882
Amortization of debt discount	135	24	151
Stock-based compensation expense	3,607	2,550	2,337
Provision for bad debts on trade receivables	359	6	14
Disposal of long term assets	2	44	0
Loss on extinguishment of debt	205	0	0
Changes in operating assets and liabilities:
Accounts receivable	(6,107)	(2,929)	(2,089)
Inventories	(3,829)	(1,071)	(1,424)
Prepaid expenses and other assets	(1,045)	(332)	47
Accounts payable and accrued liabilities	1,969	2,075	117
Deferred royalty revenue	4,932	0	0
Other long-term liabilities	(51)	(264)	28
Net cash used in operating activities	(54,450)	(43,539)	(46,826)
Cash flows from investing activities:
Acquisition of property and equipment	(4,643)	(2,614)	(4,112)
Decrease (increase) in restricted cash	3,837	1,108	(4,345)
Net cash used in investing activities	(806)	(1,506)	(8,457)
Cash flows from financing activities:
Net proceeds from issuance of preferred stock	0	21,598	73,578
Proceeds from exercise of common stock options	806	121	521
Proceeds from exercise of common stock warrant	18	0	0
Proceeds from exercise of preferred stock warrant	4,458	0	0
Proceeds from issuance of debt	0	10,000	0
Payments on notes payable	(10,278)	(2,382)	(4,496)
Payment on extinguishment of debt	(205)	0	0
Net proceeds from issuance of common stock	139,766	0	0
Net cash provided by financing activities	134,565	29,337	69,603
Foreign exchange effect on cash and cash equivalents	(24)	(613)	167
(Decrease) increase in cash and cash equivalents	79,285	(16,321)	14,487
Cash and cash equivalents, beginning of period	37,900	54,221	39,734
Cash and cash equivalents, end of period	117,185	37,900	54,221
Supplemental information:
Cash paid for income taxes	187	156	123
Cash paid for interest	1,284	162	560
Noncash investing and financing activities
Issuances of Series E-1 preferred stock warrants	$ 0	$ 177	$ 1,533