CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Revenues	$ 12,391,000	$ 16,683,000	$ 42,411,000	$ 46,657,000
Cost of revenues	6,885,000	9,247,000	23,290,000	25,738,000
Gross margin	5,506,000	7,436,000	19,121,000	20,919,000
Research and development expenses	2,408,000	2,162,000	6,950,000	6,585,000
Selling, general and administrative expenses	3,855,000	3,945,000	11,779,000	12,448,000
Income (loss) from operations	(757,000)	1,329,000	392,000	1,886,000
Interest income and other	170,000	35,000	306,000	192,000
Income (loss) before income taxes	(587,000)	1,364,000	698,000	2,078,000
Income tax expense (benefit)	(234,000)	297,000	92,000	444,000
Net income (loss)	$ (353,000)	$ 1,067,000	$ 606,000	$ 1,634,000
Net income (loss) per share – Basic	$ (0.05)	$ 0.15	$ 0.09	$ 0.23
Net income (loss) per share – Diluted	$ (0.05)	$ 0.15	$ 0.08	$ 0.23
Weighted average shares outstanding – Basic	7,117	7,041	7,108	7,012
Weighted average shares outstanding – Diluted	7,117	7,299	7,245	7,176