CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - USD ($)	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total
Balance at Dec. 31, 2018	$ 45,277	$ 21,420,886	$ 25,268,187	$ 46,734,350
Balance, shares at Dec. 31, 2018	4,527,685
Exercise of stock options	$ 328	206,264		206,592
Exercise of stock options, shares	32,810
Other share retirements	$ (59)	(27,915)	(62,023)	(89,997)
Other share retirements, shares	(5,863)
Stock-based compensation		203,333		203,333
Dividend distribution			(964,242)	(964,242)
401(K) stock match	$ 424	567,994		568,418
401(K) stock match, shares	42,405
Issuance of deferred stock awards	$ 110	(55,044)		(54,934)
Issuance of deferred stock awards, shares	10,968
Shares issued under Employee Stock Purchase Plan	$ 114	127,217		127,331
Shares issued under Employee Stock Purchase Plan, shares	11,416
Net income			2,164,832	2,164,832
Balance at Sep. 30, 2019	$ 46,194	22,442,735	26,406,754	48,895,683
Balance, shares at Sep. 30, 2019	4,619,421
Balance at Jun. 30, 2019	$ 46,041	22,223,470	25,579,114	47,848,625
Balance, shares at Jun. 30, 2019	4,604,107
Exercise of stock options	$ 25	20,675		20,700
Exercise of stock options, shares	2,500
Stock-based compensation		39,825		39,825
Dividend distribution			(322,845)	(322,845)
401(K) stock match	$ 128	158,765		158,893
401(K) stock match, shares	12,814
Net income			1,150,485	1,150,485
Balance at Sep. 30, 2019	$ 46,194	22,442,735	26,406,754	48,895,683
Balance, shares at Sep. 30, 2019	4,619,421
Balance at Dec. 31, 2019	$ 46,445	22,733,933	26,635,732	49,416,110
Balance, shares at Dec. 31, 2019	4,644,522
Exercise of stock options	$ 242	200,548		200,790
Exercise of stock options, shares	24,250
Other share retirements	$ (99)	(44,587)	(79,512)	(124,198)
Other share retirements, shares	(9,920)
Stock-based compensation		271,631		271,631
Dividend distribution			(4,148)	(4,148)
401(K) stock match	$ 282	293,693		293,975
401(K) stock match, shares	28,154
Issuance of deferred stock awards	$ 279	(72,659)		(72,380)
Issuance of deferred stock awards, shares	27,917
Shares issued under Employee Stock Purchase Plan	$ 39	36,246		36,285
Shares issued under Employee Stock Purchase Plan, shares	3,902
Net income			923,036	923,036
Balance at Sep. 30, 2020	$ 47,188	23,418,805	27,475,108	50,941,101
Balance, shares at Sep. 30, 2020	4,718,825
Balance at Jun. 30, 2020	$ 47,068	23,096,660	25,626,591	48,770,319
Balance, shares at Jun. 30, 2020	4,706,814
Stock-based compensation		203,966		203,966
Dividend distribution			(495)	(495)
401(K) stock match	$ 97	118,202		118,299
401(K) stock match, shares	9,657
Issuance of deferred stock awards	$ 23	(23)
Issuance of deferred stock awards, shares	2,354
Net income			1,849,012	1,849,012
Balance at Sep. 30, 2020	$ 47,188	$ 23,418,805	$ 27,475,108	$ 50,941,101
Balance, shares at Sep. 30, 2020	4,718,825