Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 24,286	$ 26,136
Short-term investments	26,406	51,419
Accounts receivable, net	17,387	19,564
Inventory, net	17,596	20,057
Prepaid expenses and other	5,934	4,745
Total current assets	91,609	121,921
Restricted cash	0	143
Property and equipment, net	14,453	14,057
Other assets	655	641
Total assets	106,717	136,762
Current liabilities:
Accounts payable	5,107	4,092
Accrued liabilities	3,801	4,507
Accrued compensation and other employee benefits	7,977	8,634
Customer deposits	9,502	8,945
Deferred revenue, current portion	9,878	9,229
Deferred rent, current portion	582	512
Total current liabilities	36,847	35,919
Deferred revenue, net of current portion	3,264	3,304
Deferred rent and other long-term liabilities	8,263	8,499
Long-term debt, net of debt issuance costs	49,725	48,931
Total liabilities	98,099	96,653
Commitment and contingencies
Stockholders’ equity:
Preferred stock, $0.0001 par value, 15,000 shares authorized; none issued	0	0
Common stock, $0.0001 par value, 150,000 shares authorized; 25,785 and 25,421 shares issued and outstanding at June 30, 2018 and December 31, 2017, respectively	3	2
Additional paid-in capital	362,340	353,308
Accumulated other comprehensive loss	(66)	(99)
Accumulated deficit	(353,659)	(313,102)
Total stockholders’ equity	8,618	40,109
Total liabilities and stockholders’ equity	$ 106,717	$ 136,762