Statements of Changes in Stockholders' Equity (Unaudited) - USD ($)	Common Stock [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2017	4,594,319
Balance at Dec. 31, 2017	$ 459,432	$ 466,025	$ 10,471,185	$ 11,396,642
Net income			1,059,862	1,059,862
Balance (in shares) at Mar. 31, 2018	4,594,319
Balance at Mar. 31, 2018	$ 459,432		11,997,072	12,456,504
Reclassification of accumulated other comprehensive income to retained earnings in accordance with ASU 2016-01 (See Note 6)		(466,025)	466,025
Balance (in shares) at Dec. 31, 2017	4,594,319
Balance at Dec. 31, 2017	$ 459,432	466,025	10,471,185	11,396,642
Net income				2,452,524
Balance (in shares) at Jun. 30, 2018	4,594,319
Balance at Jun. 30, 2018	$ 459,432		11,092,573	11,552,005
Balance (in shares) at Mar. 31, 2018	4,594,319
Balance at Mar. 31, 2018	$ 459,432		11,997,072	12,456,504
Net income			1,392,662	1,392,662
Dividends declared & paid ($0.55 per share)			2,291,294	2,291,294
Dividends declared, not paid ($0.55 per share)			5,867	5,867
Balance (in shares) at Jun. 30, 2018	4,594,319
Balance at Jun. 30, 2018	$ 459,432		11,092,573	11,552,005
Dividends declared & paid ($0.50 per share)			(2,291,294)	(2,291,294)
Dividends declared, not paid ($0.50 per share)			(5,867)	(5,867)
Balance (in shares) at Dec. 31, 2018	4,594,319
Balance at Dec. 31, 2018	$ 459,432		10,465,506	10,924,938
Net income			1,222,694	1,222,694
Balance (in shares) at Mar. 31, 2019	4,594,319
Balance at Mar. 31, 2019	$ 459,432		11,688,200	12,147,632
Balance (in shares) at Dec. 31, 2018	4,594,319
Balance at Dec. 31, 2018	$ 459,432		10,465,506	10,924,938
Net income				2,301,504
Balance (in shares) at Jun. 30, 2019	4,594,319
Balance at Jun. 30, 2019	$ 459,432		10,240,134	10,699,566
Balance (in shares) at Mar. 31, 2019	4,594,319
Balance at Mar. 31, 2019	$ 459,432		11,688,200	12,147,632
Net income			1,078,810	1,078,810
Dividends declared & paid ($0.55 per share)			(2,524,946)	(2,524,946)
Dividends declared, not paid ($0.55 per share)			(1,930)	(1,930)
Balance (in shares) at Jun. 30, 2019	4,594,319
Balance at Jun. 30, 2019	$ 459,432		10,240,134	10,699,566
Dividends declared & paid ($0.50 per share)			2,524,946	2,524,946
Dividends declared, not paid ($0.50 per share)			$ 1,930	$ 1,930