CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (UNAUDITED) - USD ($)	Common Stock [Member]	Additional Paid in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Beginning Balance at Dec. 31, 2017		$ 37,236,566	$ 8,847,164	$ (2,247,415)	$ (1,071,680)	$ 42,764,635
Beginning Balance (in shares) at Dec. 31, 2017	4,989,279
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			1,612,230			1,612,230
Other comprehensive income (loss)					(1,047,998)	(1,047,998)
Exercise of stock options		18,768				18,768
Exercise of stock options (in shares)	1,600
Stock-based compensation expense		18,882				18,882
Cash dividends			(749,668)			(749,668)
Common stock dividend, 10%		9,334,342	(9,334,342)
Common stock dividend, 10% (in shares)	499,088
Ending Balance at Mar. 31, 2018		46,608,558	375,384	(2,247,415)	(2,119,678)	42,616,849
Ending Balance (in shares) at Mar. 31, 2018	5,489,967
Beginning Balance at Dec. 31, 2017		37,236,566	8,847,164	(2,247,415)	(1,071,680)	42,764,635
Beginning Balance (in shares) at Dec. 31, 2017	4,989,279
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income						5,116,740
Other comprehensive income (loss)						(1,870,267)
Ending Balance at Sep. 30, 2018		46,838,852	1,670,893	(2,268,264)	(2,941,947)	43,299,534
Ending Balance (in shares) at Sep. 30, 2018	5,500,616
Beginning Balance at Mar. 31, 2018		46,608,558	375,384	(2,247,415)	(2,119,678)	42,616,849
Beginning Balance (in shares) at Mar. 31, 2018	5,489,967
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			1,726,357			1,726,357
Other comprehensive income (loss)					(389,454)	(389,454)
Exercise of stock options		104,528		(20,849)		83,679
Exercise of stock options (in shares)	10,649
Stock-based compensation expense		18,881				18,881
Cash dividends			(831,578)			(831,578)
Ending Balance at Jun. 30, 2018		46,731,967	1,270,163	(2,268,264)	(2,509,132)	43,224,734
Ending Balance (in shares) at Jun. 30, 2018	5,500,616
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			1,778,153			1,778,153
Other comprehensive income (loss)					(432,815)	(432,815)
Exercise of stock options		91,122				91,122
Stock-based compensation expense		15,763				15,763
Cash dividends			(1,377,423)			(1,377,423)
Ending Balance at Sep. 30, 2018		46,838,852	1,670,893	(2,268,264)	(2,941,947)	43,299,534
Ending Balance (in shares) at Sep. 30, 2018	5,500,616
Beginning Balance at Dec. 31, 2018		46,857,734	2,650,296	(2,268,264)	(1,777,205)	$ 45,462,561
Beginning Balance (in shares) at Dec. 31, 2018	5,510,917					5,510,917
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			1,689,264			$ 1,689,264
Other comprehensive income (loss)					991,936	991,936
Exercise of stock options		51,265				51,265
Exercise of stock options (in shares)	5,808
Stock-based compensation expense		18,881				18,881
Cash dividends			(882,676)			(882,676)
Ending Balance at Mar. 31, 2019		46,927,880	3,456,884	(2,268,264)	(785,269)	47,331,231
Ending Balance (in shares) at Mar. 31, 2019	5,516,725
Beginning Balance at Dec. 31, 2018		46,857,734	2,650,296	(2,268,264)	(1,777,205)	$ 45,462,561
Beginning Balance (in shares) at Dec. 31, 2018	5,510,917					5,510,917
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income						$ 5,544,902
Other comprehensive income (loss)						2,321,352
Ending Balance at Sep. 30, 2019		47,110,889	4,990,680	(2,325,225)	544,147	$ 50,320,491
Ending Balance (in shares) at Sep. 30, 2019	5,530,001					5,530,001
Beginning Balance at Mar. 31, 2019		46,927,880	3,456,884	(2,268,264)	(785,269)	$ 47,331,231
Beginning Balance (in shares) at Mar. 31, 2019	5,516,725
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			1,840,847			1,840,847
Other comprehensive income (loss)					1,038,565	1,038,565
Exercise of stock options		94,977		(45,843)		49,134
Exercise of stock options (in shares)	8,553
Stock-based compensation expense		18,882				18,882
Cash dividends			(884,044)			(884,044)
Ending Balance at Jun. 30, 2019		47,041,739	4,413,687	(2,314,107)	253,296	49,394,615
Ending Balance (in shares) at Jun. 30, 2019	5,525,278
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			2,014,791			2,014,791
Other comprehensive income (loss)					290,851	290,851
Exercise of stock options		49,005		(11,118)		37,887
Exercise of stock options (in shares)	4,723
Stock-based compensation expense		20,145				20,145
Cash dividends			(1,437,798)			(1,437,798)
Ending Balance at Sep. 30, 2019		$ 47,110,889	$ 4,990,680	$ (2,325,225)	$ 544,147	$ 50,320,491
Ending Balance (in shares) at Sep. 30, 2019	5,530,001					5,530,001