Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 66,260	$ 28,513
Investments	100,218	80,648
Trade accounts receivable	1,860	1,946
Inventory	7,746	8,063
Prepaid expenses	980	850
Other current assets	576	468
Total current assets	177,640	120,488
Property and equipment, net	7,303	4,890
Intellectual property, net	114	134
Other non-current assets	208	0
Total assets	185,265	125,512
Current liabilities:
Accounts payable	1,322	2,080
Accrued liabilities	4,962	3,636
Accrued Interest	1,262	0
Deferred revenue and income	217	1,071
Total current liabilities	7,763	6,787
Other long term liabilities	53	21
Convertible notes	120,074	0
Total liabilities	127,890	6,808
Commitments and contingencies
Stockholders' equity:
Preferred shares, $0.001 par value	0	0
Common stock, $0.001 par value	54	56
Contributed capital	432,885	360,620
Treasury stock	(45,067)	0
Accumulated deficit	(330,348)	(241,972)
Accumulated other comprehensive (loss)	(149)	0
Total stockholders' equity	57,375	118,704
Total liabilities and stockholders' equity	$ 185,265	$ 125,512