Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 46,907	$ 27,186
Trade accounts receivable, net of allowance for doubtful accounts of $111 in 2021 and $111 in 2020	10,649	10,027
Inventory, net	2,498	3,144
Prepaid expenses and other current assets	2,188	1,945
Total current assets	62,242	42,302
Property and equipment, net of accumulated depreciation of $6,854 in 2021 and $6,778 in 2020	930	744
Operating lease assets	1,565	1,758
Other assets	1,564	1,527
Intangible assets, net of accumulated amortization of $8,552 in 2021 and $8,494 in 2020	831	889
Goodwill	8,362	8,362
Total assets	75,494	55,582
Current liabilities:
Accounts payable	1,251	2,869
Accrued and other expenses	5,819	7,039
Notes payable - current portion	269	0
Lease payable - current portion	847	726
Deferred revenue	5,957	6,117
Total current liabilities	14,143	16,751
Lease payable, long-term portion	860	1,075
Notes payable, long-term portion	6,703	6,960
Deferred revenue, long-term portion	420	267
Deferred tax	4	4
Total liabilities	22,130	25,057
Commitments and contingencies (Note 7)
Stockholders' equity:
Preferred stock, $0.01 par value: authorized 1,000,000 shares; none issued
Common stock, $0.01 par value: authorized 30,000,000 shares; issued 25,143,432 as of March 31, 2021 and 23,693,735 as of December 31, 2020 Outstanding 24,957,601 as of March 31, 2021 and 23,508,575 as of December 31, 2020	251	236
Additional paid-in capital	298,106	273,639
Accumulated deficit	(243,578)	(241,935)
Treasury stock at cost, 185,831 shares in 2021 and 2020	(1,415)	(1,415)
Total stockholders' equity	53,364	30,525
Total liabilities and stockholders' equity	$ 75,494	$ 55,582