Note 19 - Fair Values of Financial Instruments - Fair Value by Balance Sheet Grouping (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Financial assets:
Available-for-sale securities, at fair value	$ 33,428,658	$ 24,399,881
Reported Value Measurement [Member]
Financial assets:
Cash and due from banks	6,374,000	4,988,000
Interest-bearing deposits with banks	5,400,000	4,885,000
Available-for-sale securities, at fair value	33,429,000	24,400,000
Loans held for sale	26,884,000	15,424,000
Loans held for investment, net	282,790,000	257,896,000
Derivative IRLC's, fair value disclosure	381,000
Derivative Asset, Fair Value, Gross Asset, Total	(154,000)
Stock in financial institutions	3,910,000	3,826,000
Financial liabilities:
Demand deposits, savings and NOW deposits	187,700,000	172,512,000
Time deposits	77,539,000	63,049,000
Federal Home Loan Bank advances	67,000,000	45,000,000
Estimate of Fair Value Measurement [Member]
Financial assets:
Cash and due from banks	6,374,000	4,988,000
Interest-bearing deposits with banks	5,400,000	4,885,000
Available-for-sale securities, at fair value	33,429,000	24,400,000
Loans held for sale	26,884,000	15,424,000
Loans held for investment, net	283,466,000	257,937,000
Derivative IRLC's, fair value disclosure	381,000
Derivative Asset, Fair Value, Gross Asset, Total	(154,000)
Stock in financial institutions	3,910,000	3,826,000
Financial liabilities:
Demand deposits, savings and NOW deposits	172,049,000	168,080,000
Time deposits	77,688,000	63,076,000
Federal Home Loan Bank advances	66,653,000	45,176,000
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and due from banks	6,374,000	4,988,000
Interest-bearing deposits with banks	5,400,000	4,885,000
Available-for-sale securities, at fair value	0	0
Loans held for sale	0	0
Loans held for investment, net	0	0
Derivative IRLC's, fair value disclosure	0
Derivative Asset, Fair Value, Gross Asset, Total	0
Stock in financial institutions	0	0
Financial liabilities:
Demand deposits, savings and NOW deposits	172,049,000	168,080,000
Time deposits	0	0
Federal Home Loan Bank advances	0	0
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Financial assets:
Cash and due from banks	0	0
Interest-bearing deposits with banks	0	0
Available-for-sale securities, at fair value	33,429,000	24,400,000
Loans held for sale	26,884,000	15,424,000
Loans held for investment, net	0	0
Derivative IRLC's, fair value disclosure	0
Derivative Asset, Fair Value, Gross Asset, Total	(154,000)
Stock in financial institutions	3,910,000	3,826,000
Financial liabilities:
Demand deposits, savings and NOW deposits	0	0
Time deposits	77,688,000	63,076,000
Federal Home Loan Bank advances	66,653,000	45,176,000
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Financial assets:
Cash and due from banks	0	0
Interest-bearing deposits with banks	0	0
Available-for-sale securities, at fair value	0	0
Loans held for sale	0	0
Loans held for investment, net	283,466,000	257,937,000
Derivative IRLC's, fair value disclosure	381,000
Derivative Asset, Fair Value, Gross Asset, Total	0
Stock in financial institutions	0	0
Financial liabilities:
Demand deposits, savings and NOW deposits	0	0
Time deposits	0	0
Federal Home Loan Bank advances	$ 0	$ 0

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 borrowing from Federal Home Loan Bank (FHLBank).

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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