Note 3 - Securities - Available-for-sale Debt Securities (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Available-for-sale securities, amortized cost	$ 177,601,112	$ 159,249,817
Available-for-sale securities, gross unrealized gains	3,842,922	5,185,301
Available-for-sale securities, gross unrealized (losses)	(2,109,469)	(314,249)
Available-for-sale securities	179,334,565	164,120,869
US Government Agencies Debt Securities [Member]
Available-for-sale securities, amortized cost	7,277,937	6,282,000
Available-for-sale securities, gross unrealized gains	0	6,519
Available-for-sale securities, gross unrealized (losses)	(293,249)	(4,885)
Available-for-sale securities	6,984,688	6,283,634
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized cost	66,051,714	58,754,912
Available-for-sale securities, gross unrealized gains	2,157,557	3,241,133
Available-for-sale securities, gross unrealized (losses)	(743,209)	(26,991)
Available-for-sale securities	67,466,062	61,969,054
Corporate Debt Securities [Member]
Available-for-sale securities, amortized cost	34,682,597	30,510,893
Available-for-sale securities, gross unrealized gains	345,845	261,740
Available-for-sale securities, gross unrealized (losses)	(394,092)	(171,811)
Available-for-sale securities	34,634,350	30,600,822
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, amortized cost	6,406,588
Available-for-sale securities, gross unrealized gains	76,714
Available-for-sale securities, gross unrealized (losses)	(8,576)
Available-for-sale securities	6,474,726
Commercial Mortgage Backed Securities [Member] \| Commercial Portfolio Segment [Member]
Available-for-sale securities, amortized cost		5,399,385
Available-for-sale securities, gross unrealized gains		55,712
Available-for-sale securities, gross unrealized (losses)		(10,650)
Available-for-sale securities		5,444,447
Residential Mortgage Backed Securities [Member]
Available-for-sale securities, amortized cost	9,418,436	9,249,375
Available-for-sale securities, gross unrealized gains	208,602	228,469
Available-for-sale securities, gross unrealized (losses)	(95,228)	(25,747)
Available-for-sale securities	9,531,810	9,452,097
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale securities, amortized cost	53,763,840	49,053,252
Available-for-sale securities, gross unrealized gains	1,054,204	1,391,728
Available-for-sale securities, gross unrealized (losses)	(575,115)	(74,165)
Available-for-sale securities	$ 54,242,929	$ 50,370,815

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-SubTopic 10
-Section 50
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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