Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017		Sep. 30, 2016
Cash flows from operating activities:
Net loss	$ (26,735)		$ (14,291)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	318		78
Stock-based compensation	1,314		662
Fair value of common stock issued	260
Fair value of warrants issued			162
Non-cash interest expense	762		422
Changes in assets and liabilities:
Accounts receivable	(2,742)		(1,214)
Inventory	422		76
Prepaid expenses and other current assets	(2,151)		(70)
Other noncurrent assets	24		5
Accounts payable	483		1,045
Accrued and other liabilities	1,747		931
Other noncurrent liabilities	24
Net cash used in operating activities	(26,274)		(12,194)
Cash flows from investing activities:
Investment in limited liability company	(2,500)
Purchase of property and equipment	(810)		(224)
Net cash used in investing activities	(3,310)		(224)
Cash flows from financing activities:
Proceeds from sale of common stock, net of issuance costs	31,440		13,886
Proceeds from note payable	19,214		9,910
Repayments of note payable	(10,000)		(4,833)
Proceeds from exercise of warrant	20		92
Proceeds from exercise of stock options	31		14
Net cash provided by financing activities	40,705		19,069
Net increase in cash and cash equivalents	11,121		6,651
Cash and cash equivalents - beginning of period	8,086	[1]	7,360
Cash and cash equivalents - end of period	19,207		14,011
Supplemental disclosure:
Cash paid for interest	1,619		636
Cash paid for income taxes			1
Supplemental disclosure of cash flow information as of end of period:
Issuance of warrants in connection with note payable	940		350
Net transfer of equipment from inventory to property and equipment	362		60
Issuance of note payable in settlement of accrued interest	285
Restricted stock awards granted to employees for 2015 accrued bonuses			$ 246

[1] The condensed consolidated balance sheet as of December 31, 2016 has been derived from the audited consolidated financial statements as of that date.