Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
ASSETS
Cash and cash equivalents	$ 9,662	$ 7,094
Short-term investment securities	28,608	32,556
Accounts receivable, net of allowances of $117 and $104 at March 31, 2020 and December 31, 2019, respectively	13,918	17,380
Inventories, net	11,133	11,935
Prepaid expenses and other assets	1,568	1,842
Total current assets	64,889	70,807
Property and equipment, net	12,130	11,985
Goodwill	3,332	3,332
Intangible assets, net	0	144
Other noncurrent assets	2,748	2,969
TOTAL ASSETS	83,099	89,237
LIABILITIES AND STOCKHOLDERS’ EQUITY
Accounts payable	3,984	3,190
Accrued liabilities	5,770	9,382
Total current liabilities	9,754	12,572
Long-term liabilities	4,289	3,315
Total liabilities	14,043	15,887
Stockholders’ equity:
Common stock, $0.001 par value, 100,000,000 shares authorized, 18,456,149 and 18,611,289 shares issued and outstanding at March 31, 2020 and December 31, 2019, respectively	18	19
Additional paid-in capital	130,438	133,954
Accumulated deficit	(60,993)	(60,305)
Accumulated other comprehensive loss	(407)	(318)
Total stockholders’ equity	69,056	73,350
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 83,099	$ 89,237