Note 3 - Investment Securities - Amortized Cost and Fair Values of Securities (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Securities available for sale, amortized cost	$ 24,061,805	$ 25,577,244
Securities available for sale, gross unrealized gains	484,088	175,409
Securities available for sale, gross unrealized losses	30,136	218,886
Securities available for sale	24,515,759	25,533,767
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale, amortized cost	13,126,074	13,092,077
Securities available for sale, gross unrealized gains	339,243	116,127
Securities available for sale, gross unrealized losses		21,416
Securities available for sale	13,465,317	13,186,788
Residential Mortgage Backed Securities [Member]
Securities available for sale, amortized cost	10,935,731	12,485,167
Securities available for sale, gross unrealized gains	144,845	59,282
Securities available for sale, gross unrealized losses	30,136	197,470
Securities available for sale	$ 11,050,442	$ 12,346,979

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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