Condensed Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($)	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2018	13,502,684
Balance at Dec. 31, 2018	$ 135,000	$ 2,669,000	$ 29,390,000	$ 32,194,000
Net income			1,218,000	1,218,000	$ 1,218,000
Common stock repurchased and retired (in shares)	(255,000)
Common stock repurchased and retired	$ (2,000)	(1,006,000)		(1,008,000)
Stock-based compensation expense		122,000		122,000
Options exercised (in shares)	33,334
Options exercised		60,000		60,000
Balance (in shares) at Mar. 31, 2019	13,281,018
Balance at Mar. 31, 2019	$ 133,000	1,845,000	30,608,000	32,586,000
Balance (in shares) at Dec. 31, 2019	12,885,273				13,502,684
Balance at Dec. 31, 2019	$ 129,000	708,000	32,390,000	33,227,000	$ 33,227,000
Net income			5,342,000	5,342,000	$ 5,342,000
Common stock repurchased and retired (in shares)	(35,100)
Common stock repurchased and retired		(125,000)		(125,000)
Stock-based compensation expense		91,000		91,000
Options exercised (in shares)	712,839				712,839
Options exercised	$ 7,000	1,834,000		1,841,000
Balance (in shares) at Mar. 31, 2020	13,563,012				13,563,012
Balance at Mar. 31, 2020	$ 136,000	$ 2,508,000	$ 37,732,000	$ 40,376,000	$ 40,376,000