Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 14,051	$ 18,744
Securities available-for-sale	7,935	7,673
Accounts receivable, net	5,989	5,430
Inventories, net	3,644	3,881
Other current assets	856	697
Restricted cash	477	244
Total current assets	32,952	36,669
Property and equipment, net	4,766	4,153
Property and equipment, net	2,577	353
Goodwill	1,337	184
Other assets	269	92
Total assets	41,901	41,451
Liabilities and stockholders' equity
Accounts payable	1,423	611
Accrued compensation	3,261	3,472
Accrued warranty	176	137
Deferred revenue	1,644	1,631
Other current liabilities	1,789	1,774
Total current liabilities	8,293	7,625
Other liabilities	963	440
Total liabilities	9,256	8,065
Commitments and contingencies (Note 7)
Stockholders' equity:
Preferred stock, $0.0001 par value: 10,000,000 shares authorized; no shares issued or outstanding	0	0
Common stock, $0.0001 par value: 80,000,000 shares authorized; 18,615,945 and 18,504,279 shares issued and outstanding (net of treasury shares) at December 31, 2014 and 2013, respectively	2	2
Treasury stock, at cost; 2,588,484 shares at December 31, 2014 and 2013	(5,728)	(5,728)
Additional paid-in capital	153,769	156,968
Accumulated other comprehensive loss	(19)	(2)
Accumulated deficit	(115,379)	(117,854)
Total stockholders’ equity	32,645	33,386
Total liabilities and stockholders’ equity	$ 41,901	$ 41,451