CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities:
Net loss	$ (66,135,000)	$ (47,733,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	1,734,000	1,595,000
Amortization of intangible assets	15,000	9,000
Amortization of investment discount	(413,000)	298,000
Equity-based compensation	12,476,000	10,970,000
Amortization of debt discount and issuance costs	4,529,000	0
Loss on disposal of property and equipment	540,000	3,000
(Increase) decrease in assets:
Accounts receivable	506,000	(1,077,000)
Inventory	(5,206,000)	(7,079,000)
Prepaid expense and other	55,000	(392,000)
Other current assets	(26,000)	(277,000)
Other non-current assets	(241,000)	0
Increase (decrease) in liabilities:
Accounts payable	(524,000)	359,000
Accrued liabilities	(18,000)	780,000
Accrued interest	191,000	0
Deferred revenue and income	(918,000)	46,000
Deferred compensation	5,000	0
Net cash used in operating activities	(53,430,000)	(42,498,000)
Cash flows from investing activities:
Purchases of equipment	(842,000)	(2,055,000)
Purchases of available-for-sale securities	(115,634,000)	(68,423,000)
Sales of available-for-sale securities	3,000,000	9,522,000
Maturity of available-for-sale securities	74,496,000	30,049,000
Net cash used in investing activities	(38,980,000)	(30,907,000)
Cash flows from financing activities:
Issuance of common stock net of issuance costs	447,000	83,741,000
Exercise of options and warrants	3,710,000	4,562,000
Proceeds from issuance of convertible note	171,500,000	0
Prepayment of forward stock repurchase transaction	(45,069,000)	0
Payment of debt issuance costs	(4,992,000)	0
Net cash provided by financing activities	125,596,000	88,303,000
Effect of exchange rate on cash	(77,000)	289,000
Increase in cash and cash equivalents	33,109,000	15,187,000
Cash and cash equivalents, beginning of period	28,513,000	19,244,000
Cash and cash equivalents, end of period	61,622,000	34,431,000
Non-cash investing activities:
Transfer of instruments from inventory to property and equipment	4,061,000	0
Interest paid	2,001,000	0
Income taxes paid	$ 435,000	$ 0