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, 2017	14,290,749
Balance at Dec. 31, 2017	$ 143,000	$ 5,415,000	$ (458,000)	$ 26,223,000	$ 31,323,000
Net income				508,000	508,000
Common stock repurchased and retired (in shares)	(153,000)
Common stock repurchased and retired	$ (1,000)	(575,000)			(576,000)
Stock-based compensation expense		78,000			78,000
Options exercised (in shares)	50,000
Options exercised		77,000			77,000
Balance (in shares) at Mar. 31, 2018	14,187,749
Balance at Mar. 31, 2018	$ 142,000	4,995,000		26,273,000	31,410,000
Balance (in shares) at Dec. 31, 2017	14,290,749
Balance at Dec. 31, 2017	$ 143,000	5,415,000	(458,000)	26,223,000	31,323,000
Net income					3,007,000
Balance (in shares) at Sep. 30, 2018	13,629,583
Balance at Sep. 30, 2018	$ 136,000	3,130,000		28,772,000	32,038,000
Cumulative-effect adjustment of change in accounting for unrealized loss on marketable securities			458,000	(458,000)
Balance (in shares) at Mar. 31, 2018	14,187,749
Balance at Mar. 31, 2018	$ 142,000	4,995,000		26,273,000	31,410,000
Net income				959,000	959,000
Common stock repurchased and retired (in shares)	(300,000)
Common stock repurchased and retired	$ (4,000)	(1,037,000)			(1,041,000)
Stock-based compensation expense		118,000			118,000
Options exercised (in shares)	21,667
Options exercised	$ 1,000	42,000			43,000
Balance (in shares) at Jun. 30, 2018	13,909,416
Balance at Jun. 30, 2018	$ 139,000	4,118,000		27,232,000	31,489,000
Net income				1,540,000	1,539,000
Common stock repurchased and retired (in shares)	(340,000)
Common stock repurchased and retired	$ (3,000)	(1,208,000)			(1,211,000)
Stock-based compensation expense		116,000			116,000
Options exercised (in shares)	60,167
Options exercised		104,000			104,000
Balance (in shares) at Sep. 30, 2018	13,629,583
Balance at Sep. 30, 2018	$ 136,000	3,130,000		28,772,000	$ 32,038,000
Balance (in shares) at Dec. 31, 2018	13,502,684				13,502,684	[1]
Balance at Dec. 31, 2018	$ 135,000	2,669,000		29,390,000	$ 32,194,000	[2]
Net income				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, 2018	13,502,684				13,502,684	[1]
Balance at Dec. 31, 2018	$ 135,000	2,669,000		29,390,000	$ 32,194,000	[2]
Net income					$ 2,665,000
Options exercised (in shares)					49,833
Balance (in shares) at Sep. 30, 2019	13,004,507				13,004,507
Balance at Sep. 30, 2019	$ 130,000	1,058,000		32,055,000	$ 33,243,000
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
Net income				1,010,000	1,010,000
Common stock repurchased and retired (in shares)	(172,000)
Common stock repurchased and retired	$ (2,000)	(626,000)			(628,000)
Stock-based compensation expense		138,000			138,000
Options exercised
Balance (in shares) at Jun. 30, 2019	13,109,018
Balance at Jun. 30, 2019	$ 131,000	1,357,000		31,618,000	33,106,000
Net income				437,000	437,000
Common stock repurchased and retired (in shares)	(121,010)
Common stock repurchased and retired	$ (1,000)	(427,000)			(428,000)
Stock-based compensation expense		93,000			93,000
Options exercised (in shares)	16,499
Options exercised		35,000			$ 35,000
Balance (in shares) at Sep. 30, 2019	13,004,507				13,004,507
Balance at Sep. 30, 2019	$ 130,000	$ 1,058,000		$ 32,055,000	$ 33,243,000

[1] The condensed consolidated balance sheet as of December 31, 2018 has been prepared using information from the audited consolidated balance sheet as of that date.

[2] The condensed consolidated balance sheet as of December 31, 2018 has been prepared using information from the audited consolidated balance sheet as of that date.