Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 20,685	$ 21,446
Accounts receivable, net	8,737	4,734
Inventories	6,318	6,326
Prepaid expenses and other current assets	2,675	3,467
Total current assets	38,415	35,973
Property and equipment, net	15,880	15,229
Intangible assets, net	698	744
Goodwill	9,473	9,123
Other assets	73	151
Total assets	64,539	61,220
Liabilities and stockholders’ equity
Accounts payable	5,079	4,038
Accrued expenses and other	3,916	5,615
Deferred revenue	635	6,141
Current portion of long-term debt	572	546
Total current liabilities	10,202	16,340
Long-term debt, net of current portion	3,232	3,253
Other non-current liabilities	85	115
Total liabilities	13,519	19,708
Stockholders’ equity:
Common stock $0.01 par value; 150,000 shares authorized; 12,521 issued and 11,101 outstanding at March 31, 2018 and 12,257 issued and 10,844 outstanding at December 31, 2017	125	123
Additional paid-in capital	294,061	292,108
Treasury stock (at cost), 1,420 shares at March 31, 2018 and 1,413 shares at December 31, 2017	(8,661)	(8,601)
Accumulated deficit	(232,288)	(238,961)
Accumulated other comprehensive loss	(2,217)	(3,157)
Total stockholders’ equity	51,020	41,512
Total liabilities and stockholders’ equity	$ 64,539	$ 61,220