CONDENSED STATEMENTS OF CASH FLOWS - USD ($)	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Operating Activities:
Net income (loss)	$ (2,562,000)	$ 993,000
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	1,192,000	860,000
Changes in allowance for doubtful accounts	1,000	(16,000)
Deferred income tax expense	(443,000)	(9,000)
Stock-based compensation expense	378,000	277,000
Changes in operating assets and liabilities:
Accounts receivable	2,324,000	586,000
Inventories	10,000	(22,000)
Income tax receivable	(2,000)	266,000
Prepaid expenses and other	(17,000)	80,000
Accounts payable	(1,039,000)	408,000
Accrued liabilities	(2,031,000)	253,000
Accrued income taxes	23,000	23,000
Deferred revenue	88,000	381,000
Net cash provided by (used in) operating activities	(2,078,000)	4,080,000
Investing Activities:
Purchases of property and equipment	(361,000)	(877,000)
Purchase of investments	(4,981,000)	0
Proceeds from sale of held to maturity investments	4,981,000	0
Net cash used in investing activities	(361,000)	(877,000)
Financing Activities:
Cash dividends paid ($0.70 per share)	(14,000)	(14,000)
Proceeds from issuance of common stock	108,000	49,000
Repurchase of common stock upon vesting of restricted stock awards	(35,000)	(74,000)
Repurchase of common stock, net	0	(269,000)
Net cash provided by (used in) financing activities	59,000	(308,000)
Increase (decrease) in cash and cash equivalents	(2,380,000)	2,895,000
Cash and cash equivalents at beginning of period	10,160,000	4,695,000
Cash and cash equivalents at end of period	7,780,000	7,590,000
Supplemental disclosures for cash flow information:
Cash paid during the period for income taxes	6,000	84,000
Non-cash investing and financing activities:
Purchases of property and equipment included in accounts payable	$ 0	$ 96,000