Consolidated Statements of Shareholders' Equity - USD ($)	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2016	15,411,556
Balance at Dec. 31, 2016	$ 154,000	$ 9,990,000	$ (204,000)	$ 22,724,000	$ 32,664,000
Common stock repurchased and retired (in shares)	(1,232,476)				(1,232,476)
Common stock repurchased and retired	$ (12,000)	(4,214,000)			$ (4,226,000)
Share-based compensation expense		296,000			$ 296,000
Options exercised (in shares)	111,669				111,669
Options exercised	$ 1,000	209,000			$ 210,000
Net income				2,633,000	2,633,000
Other comprehensive loss			(254,000)		$ (254,000)
Balance (in shares) at Dec. 31, 2017	14,290,749				14,290,749
Balance at Dec. 31, 2017	$ 143,000	5,415,000	(458,000)	26,223,000	$ 31,323,000
Cumulative-effect adjustment of change in accounting for stock-based compensation		(866,000)		866,000
Cumulative-effect adjustment of change in accounting for unrealized loss on marketable securities		(866,000)		866,000
Common stock repurchased and retired (in shares)	(999,900)				(999,900)
Common stock repurchased and retired	$ (10,000)	(3,570,000)			$ (3,580,000)
Share-based compensation expense		432,000			$ 432,000
Options exercised (in shares)	211,835				211,835
Options exercised	$ 2,000	392,000			$ 394,000
Net income				3,625,000	$ 3,625,000
Balance (in shares) at Dec. 31, 2018	13,502,684				13,502,684
Balance at Dec. 31, 2018	$ 135,000	$ 2,669,000		29,390,000	$ 32,194,000
Cumulative-effect adjustment of change in accounting for stock-based compensation			458,000	(458,000)
Cumulative-effect adjustment of change in accounting for unrealized loss on marketable securities			$ 458,000	$ (458,000)