Consolidated Statements of Stockholders' Equity - USD ($)	Common Stock [Member]	Additional Paid in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Total
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Adjustments to prior periods from adopting ASC606 | ASU 2014-09 [Member]	$ 0	$ 0	$ 10,184,335	$ 0	$ 10,184,335
Balances at Dec. 31, 2017	$ 7,600	33,468,323	41,939,115	(7,898,200)	67,516,838
Balances (in shares) at Dec. 31, 2017	7,600,167
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon stock option exercise	$ 138	2,570,692	0	0	2,570,830
Issuance of common stock upon stock option exercise (in shares)	138,000
Stock compensation expense	$ 0	263,431	0	0	263,431
Repurchases of common stock	0	0	0	(3,000,183)	(3,000,183)
Net income	0	0	20,053,269	0	20,053,269
Balances at Dec. 31, 2018	$ 7,738	36,302,446	72,176,719	(10,898,383)	$ 97,588,520
Balances (in shares) at Dec. 31, 2018	7,738,167				7,275,902
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon stock option exercise	$ 75	2,191,741	0	0	$ 2,191,816
Issuance of common stock upon stock option exercise (in shares)	75,063
Stock compensation expense	$ 0	861,610	0	0	861,610
Repurchases of common stock	0	0	0	(620,652)	(620,652)
Net income	0	0	24,469,808	0	24,469,808
Balances at Dec. 31, 2019	$ 7,813	$ 39,355,797	$ 96,646,527	$ (11,519,035)	$ 124,491,102
Balances (in shares) at Dec. 31, 2019	7,813,230				7,339,578