Note 3 - Securities - Available-for-sale Debt Securities (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Available-for-sale securities, amortized cost	$ 159,249,817	$ 117,152,760
Available-for-sale securities, gross unrealized gains	5,185,301	1,468,000
Available-for-sale securities, gross unrealized (losses)	(314,249)	(375,446)
Available-for-sale securities	164,120,869	118,245,314
US Government Agencies Debt Securities [Member]
Available-for-sale securities, amortized cost	6,282,000	2,499,755
Available-for-sale securities, gross unrealized gains	6,519	0
Available-for-sale securities, gross unrealized (losses)	(4,885)	(11,962)
Available-for-sale securities	6,283,634	2,487,793
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized cost	58,754,912	35,625,038
Available-for-sale securities, gross unrealized gains	3,241,133	675,382
Available-for-sale securities, gross unrealized (losses)	(26,991)	(125,693)
Available-for-sale securities	61,969,054	36,174,727
Corporate Debt Securities [Member]
Available-for-sale securities, amortized cost	30,510,893	15,395,190
Available-for-sale securities, gross unrealized gains	261,740	154,942
Available-for-sale securities, gross unrealized (losses)	(171,811)	(14,945)
Available-for-sale securities	30,600,822	15,535,187
Commercial Mortgage Backed Securities [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
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Available-for-sale securities, amortized cost		13,788,728
Available-for-sale securities, gross unrealized gains		52,035
Available-for-sale securities, gross unrealized (losses)		(29,392)
Available-for-sale securities		13,811,371
Residential Mortgage Backed Securities [Member]
Available-for-sale securities, amortized cost	9,249,375
Available-for-sale securities, gross unrealized gains	228,469
Available-for-sale securities, gross unrealized (losses)	(25,747)
Available-for-sale securities	9,452,097
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale securities, amortized cost	49,053,252	49,844,049
Available-for-sale securities, gross unrealized gains	1,391,728	585,641
Available-for-sale securities, gross unrealized (losses)	(74,165)	(193,454)
Available-for-sale securities	$ 50,370,815	$ 50,236,236

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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Amortized cost of 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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