Note 3 - Investment Securities - Securities With Gross Unrealized Losses (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Securities available for sale, less than 12 months, fair value	$ 1,912,778	$ 4,696,851
Securities available for sale, less than 12 months, unrealized losses	6,049	34,876
Securities available for sale, 12 months or more, fair value	2,943,044	7,380,043
Securities available for sale, 12 months or more, unrealized losses	24,087	184,010
Securities available for sale, fair value	4,855,822	12,076,894
Securities available for sale, unrealized losses	30,136	218,886
Residential Mortgage Backed Securities [Member]
Securities available for sale, less than 12 months, fair value	1,912,778	2,865,546
Securities available for sale, less than 12 months, unrealized losses	6,049	25,266
Securities available for sale, 12 months or more, fair value	2,943,044	6,034,053
Securities available for sale, 12 months or more, unrealized losses	24,087	172,204
Securities available for sale, fair value	4,855,822	8,899,599
Securities available for sale, unrealized losses	$ 30,136	197,470
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale, less than 12 months, fair value		1,831,305
Securities available for sale, less than 12 months, unrealized losses		9,610
Securities available for sale, 12 months or more, fair value		1,345,990
Securities available for sale, 12 months or more, unrealized losses		11,806
Securities available for sale, fair value		3,177,295
Securities available for sale, unrealized losses		$ 21,416

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
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-Name Accounting Standards Codification
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