Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	[1]
Current assets:
Cash and cash equivalents	$ 30,213	$ 20,730
Accounts receivable, net of allowance for doubtful accounts of $253 and $221 as of June 30, 2018 and December 31, 2017, respectively	7,241	6,213
Inventory	4,161	2,390
Prepaid expenses and other current assets	3,024	2,741
Total current assets	44,639	32,074
Property and equipment, net	1,931	1,303
Investment in limited liability company	2,093	2,500
Other assets	188	202
Total assets	48,851	36,079
Current liabilities:
Accounts payable	4,867	4,799
Accrued liabilities	5,258	4,605
Total current liabilities	10,125	9,404
Note payable, noncurrent portion	29,724	28,948
Other noncurrent liabilities	305	327
Total liabilities	40,154	38,679
Commitments and contingences (Note 7)
Stockholders’ equity (deficit):
Common stock, $0.0001 par value; 75,000,000 shares authorized as of June 30, 2018 and December 31, 2017; 31,466,508 and 19,503,558 shares issued and outstanding as of June 30, 2018 and December 31, 2017, respectively	3	2
Additional paid-in capital	138,283	102,979
Accumulated deficit	(129,589)	(105,581)
Total stockholders’equity (deficit)	8,697	(2,600)
Total liabilities and stockholders’ equity (deficit)	$ 48,851	$ 36,079

[1] The condensed consolidated balance sheet as of December 31, 2017 has been derived from the audited consolidated financial statements as of that date.