Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 20,994	$ 13,901
Accounts receivable, net of allowances of $37 and $263 at December 31, 2016 and 2015, respectively	6,573	7,538
Inventories	5,621	3,623
Prepaid expenses and other current assets	1,539	872
Total current assets	34,727	25,934
Property and equipment, net	13,366	12,850
Intangible assets, net	969	1,598
Goodwill	8,342	10,010
Other assets	167	185
Total assets	57,571	50,577
Liabilities, contingently redeemable preferred stock, and Stockholders’ equity
Accounts payable	3,893	2,004
Accrued expenses and other	5,271	3,430
Deferred revenue	5,624	4,167
Notes payable	204	238
Total current liabilities	14,992	9,839
Deferred revenue, net of current portion		710
Notes payable, net of current portion	2,203	2,897
Deferred rent	56	69
Total liabilities	17,251	13,515
Commitments and contingencies (Note 8)
Contingently redeemable series C preferred stock, 0.55 shares issued and outstanding (liquidation preference of $550)	550	550
Stockholders’ equity:
Preferred stock, $.01 par value; 1,000 shares authorized Series B convertible preferred stock, 0.13 shares issued and outstanding (liquidation preference of $13)
Common stock $.01 par value; 150,000 shares authorized; 12,257 issued and 10,844 outstanding at December 31, 2016 and 12,215 shares issued and 10,802 outstanding at December 31, 2015	123	122
Additional paid-in capital	290,636	289,464
Treasury stock (at cost), 1,413 shares at December 31, 2016 and 2015	(8,601)	(8,601)
Accumulated deficit	(237,360)	(243,311)
Accumulated other comprehensive income loss	(5,028)	(1,162)
Total stockholders’ equity	39,770	36,512
Total liabilities, contingently redeemable preferred stock, and Stockholders’ equity	$ 57,571	$ 50,577