Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($)	Common Stock [Member] Common Class A [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Common Stock [Member] Common Class A [Member]	Common Stock [Member] Common Class B [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Common Stock [Member] Common Class B [Member]	Additional Paid-in Capital [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member] Common Class A [Member]	Treasury Stock [Member] Common Class B [Member]	Treasury Stock [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Treasury Stock [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]	Retained Earnings [Member]	Common Stock Including Additional Paid in Capital [Member] Common Class A [Member]	Common Stock Including Additional Paid in Capital [Member] Common Class B [Member]	Common Stock Outstanding [Member] Common Class A [Member]	Common Stock Outstanding [Member] Common Class B [Member]	Cumulative Effect, Period of Adoption, Adjustment [Member]	Total
Balance at Dec. 31, 2018		$ 2,641,300		$ 710,272		$ 1,741,901				$ (1,905,780)	$ (73,126)	$ 9,577,792					$ (73,126)	$ 12,765,485
Share-based compensation expense		61,342																61,342
Stock awards		204,700																204,700
Net Income												3,576,937						3,576,937
Balance (in shares) at Dec. 31, 2018							37,208	182,435					2,161,014	779,283	2,123,806	596,848
Stock awards (in shares)													39,000		39,000
Repurchase of shares (in shares)
Balance at Jun. 30, 2019		2,907,342		710,272		1,741,901				(1,905,780)		13,081,603						16,535,338
Balance (in shares) at Jun. 30, 2019							37,208	182,435					2,200,014	779,283	2,162,806	596,848
Balance at Mar. 31, 2019		2,865,159		710,272		1,741,901				(1,905,780)		11,250,124						14,661,676
Share-based compensation expense		42,183																42,183
Stock awards
Repurchase of shares
Net Income												1,831,479						1,831,479
Balance (in shares) at Mar. 31, 2019							37,208	182,435					2,196,014	779,283	2,158,806	596,848
Stock awards (in shares)													4,000		4,000
Repurchase of shares (in shares)
Balance at Jun. 30, 2019		2,907,342		710,272		1,741,901				(1,905,780)		13,081,603						16,535,338
Balance (in shares) at Jun. 30, 2019							37,208	182,435					2,200,014	779,283	2,162,806	596,848
Balance at Dec. 31, 2019		3,599,806		1,465,522		1,741,901				(1,905,780)		16,527,083						21,428,532
Share-based compensation expense		55,758																55,758
Stock awards		211,050																211,050
Repurchase of shares										(29,032)								(29,032)
Net Income												2,304,407						2,304,407
Balance (in shares) at Dec. 31, 2019							37,208	182,435					2,576,837	954,283	2,539,629	771,848
Stock awards (in shares)													15,000		15,000
Repurchase of shares (in shares)							1,727								(1,727)
Balance at Jun. 30, 2020		3,866,614		1,465,522		1,741,901				(1,934,812)		18,831,490						23,970,715
Balance (in shares) at Jun. 30, 2020							38,935	182,435					2,591,837	954,283	2,552,902	771,848
Balance at Mar. 31, 2020		3,636,272		1,465,522		1,741,901				(1,905,780)		18,602,653						23,540,568
Share-based compensation expense		19,292																19,292
Stock awards		211,050																211,050
Repurchase of shares										(29,032)								(29,032)
Net Income												228,837						228,837
Balance (in shares) at Mar. 31, 2020							37,208	182,435					2,576,837	954,283	2,539,629	771,848
Stock awards (in shares)													15,000		15,000
Repurchase of shares (in shares)							1,727								(1,727)
Balance at Jun. 30, 2020		$ 3,866,614		$ 1,465,522		$ 1,741,901				$ (1,934,812)		$ 18,831,490						$ 23,970,715
Balance (in shares) at Jun. 30, 2020							38,935	182,435					2,591,837	954,283	2,552,902	771,848