Condensed Consolidated Balance Sheets - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Current assets
Cash and cash equivalents	$ 9,302,000	$ 11,965,000
Marketable securities	18,028,000	16,304,000
Trade accounts receivable, net of allowance for doubtful accounts of $862 and $751, as of March 31, 2020 and December 31, 2019, respectively	6,371,000	6,555,000
Other current assets	3,324,000	2,255,000
Total current assets	37,025,000	37,079,000
Marketable securities, long-term	43,294,000	41,947,000
Equity method investments	623,000	872,000
Fixed assets, net	5,698,000	5,974,000
Operating lease right-of-use asset	2,525,000	2,633,000
Other long-term assets	160,000	251,000
Total assets	89,325,000	88,756,000
Current liabilities
Accounts payable	2,855,000	1,581,000
Accrued liabilities	2,024,000	1,333,000
Income tax payable	56,000	24,000
Contract liabilities	444,000	365,000
Operating lease liabilities, short-term	431,000	420,000
Total current liabilities	5,810,000	3,723,000
Operating lease liabilities, long-term	2,143,000	2,256,000
Total liabilities	7,953,000	5,979,000
Commitments and contingencies (Note 8)
Stockholders’ equity
Common stock, $0.0001 par value per share, 50,000 shares authorized, 21,672 and 21,483 shares issued and outstanding at March 31, 2020 and December 31, 2019, respectively	2,000	2,000
Preferred stock, $0.0001 par value per share, 1,000 shares authorized, no shares issued or outstanding at March 31, 2020 and December 31, 2019
Additional paid-in capital	146,948,000	146,058,000
Accumulated other comprehensive income (loss)	(193,000)	146,000
Accumulated deficit	(65,385,000)	(63,429,000)
Total stockholders’ equity	81,372,000	82,777,000
Total liabilities and stockholders’ equity	$ 89,325,000	$ 88,756,000