Note 20 - Fair Values of Financial Instruments - Fair Value by Balance Sheet Grouping (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Available-for-sale securities, fair value	$ 44,517,178	$ 33,428,658
Reported Value Measurement [Member]
Cash and due from banks	4,496,000	6,374,000
Interest-bearing deposits with banks	24,990,000	5,400,000
Available-for-sale securities, fair value	44,517,000	33,429,000
Loans held for investment, net	291,739,000	282,790,000
Stock in financial institutions	4,017,000	3,910,000
Demand deposits, savings and NOW deposits	222,509,000	187,700,000
Time deposits	81,388,000	77,539,000
Federal Home Loan Bank advances	40,000,000	67,000,000
Loans held for sale		26,884,000
Derivative IRLCs, fair value disclosure		381,000
Derivative forward commitments		(154,000)
Estimate of Fair Value Measurement [Member]
Cash and due from banks	4,496,000	6,374,000
Interest-bearing deposits with banks	24,990,000	5,400,000
Available-for-sale securities, fair value	44,517,000	33,429,000
Loans held for investment, net	292,246,000	283,466,000
Stock in financial institutions	4,017,000	3,910,000
Demand deposits, savings and NOW deposits	214,611,000	172,049,000
Time deposits	81,638,000	77,688,000
Federal Home Loan Bank advances	40,075,000	66,653,000
Loans held for sale		26,884,000
Derivative IRLCs, fair value disclosure		381,000
Derivative forward commitments		(154,000)
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and due from banks	4,496,000	6,374,000
Interest-bearing deposits with banks	24,990,000	5,400,000
Available-for-sale securities, fair value	0	0
Loans held for investment, net		0
Stock in financial institutions	0	0
Demand deposits, savings and NOW deposits	214,611,000	172,049,000
Time deposits		0
Federal Home Loan Bank advances		0
Loans held for sale
Derivative IRLCs, fair value disclosure
Derivative forward commitments
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and due from banks	0	0
Interest-bearing deposits with banks	0	0
Available-for-sale securities, fair value	44,517,000	33,429,000
Loans held for investment, net		0
Stock in financial institutions	4,017,000	3,910,000
Demand deposits, savings and NOW deposits		0
Time deposits	81,638,000	77,688,000
Federal Home Loan Bank advances	40,075,000	66,653,000
Loans held for sale		26,884,000
Derivative IRLCs, fair value disclosure
Derivative forward commitments		(154,000)
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and due from banks	0	0
Interest-bearing deposits with banks	0	0
Available-for-sale securities, fair value	0	0
Loans held for investment, net	292,246,000	283,466,000
Stock in financial institutions	0	0
Demand deposits, savings and NOW deposits		0
Time deposits		0
Federal Home Loan Bank advances		0
Loans held for sale
Derivative IRLCs, fair value disclosure		381,000
Derivative forward commitments

Fair value portion of cash and due from banks.

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Fair value portion of demand deposits and deposits in interest-bearing transaction accounts at banks or savings and loans, that are restricted in regard to ownership and can usually only be held by individuals, nonprofit entities and governments. Negotiable order of withdrawal accounts differ from money market demand accounts as they typically have higher reserve requirements and no limit on the number of checks that can be written.

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The amount represents the interest bearing deposits in banks and fair value disclosure.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Fair value portion of investments accounted under the cost method.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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