Note 13 - Fair Value and Interest Rate Risk - Financial Assets and Liabilities (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Fair value, total	$ 57,893,000	$ 49,262,000
SBA servicing assets	391,000
Reported Value Measurement [Member]
Financial assets, total	831,547,000	826,476,000
Financial liabilities, total	815,152,000	808,228,000
Estimate of Fair Value Measurement [Member]
Financial assets, total	828,773,000	823,887,000
Financial liabilities, total	822,751,000	817,066,000
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Brokered Deposits [Member]
Deposits	18,456,000	41,287,000
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Cash and Due from Banks [Member]
Cash and cash equivalents	2,593,000	3,006,000
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Interest-bearing Deposits [Member]
Cash and cash equivalents	81,681,000	31,630,000
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Brokered Deposits [Member]
Deposits	18,675,000	41,643,000
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Cash and Due from Banks [Member]
Cash and cash equivalents	2,593,000	3,006,000
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Interest-bearing Deposits [Member]
Cash and cash equivalents	81,681,000	31,630,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member]
Fair value, total	57,893,000	49,262,000
Other investments	4,450,000	4,450,000
Federal Reserve Bank stock	2,744,000	2,783,000
Federal Home Loan Bank stock	4,503,000	4,503,000
Loans held for sale	2,829,000	1,217,000
Other Real Estate Owned	1,216,000	1,906,000
Accrued interest receivable	6,270,000	6,620,000
FHLB borrowings	90,000,000	90,000,000
Senior notes	11,946,000	11,927,000
Subordinated debt	9,789,000	9,782,000
Junior subordinated debt owed to unconsolidated trust	8,112,000	8,110,000
Accrued interest payable	693,000	572,000
Interest rate swap liability	791,000	1,187,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Demand Deposits [Member]
Deposits	173,520,000	158,676,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Savings Deposits [Member]
Deposits	103,025,000	98,635,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Money Market Deposits [Member]
Deposits	131,844,000	146,389,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Negotiable Order of Withdrawal (NOW) Accounts [Member]
Deposits	34,433,000	30,529,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Time Deposits [Member]
Deposits	231,600,000	210,140,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Interest Rate Swap [Member]
Interest rate swap receivable	791,000	1,187,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member]
Fair value, total	57,893,000	49,262,000
Other investments	4,450,000	4,450,000
Federal Reserve Bank stock	2,744,000	2,783,000
Federal Home Loan Bank stock	4,503,000	4,503,000
Loans held for sale	3,008,000	1,343,000
Other Real Estate Owned	1,216,000	1,906,000
Accrued interest receivable	6,270,000	6,620,000
FHLB borrowings	96,322,000	97,293,000
Senior notes	12,022,000	12,028,000
Subordinated debt	10,072,000	10,125,000
Junior subordinated debt owed to unconsolidated trust	8,112,000	8,110,000
Accrued interest payable	693,000	572,000
Interest rate swap liability	791,000	1,187,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Demand Deposits [Member]
Deposits	173,520,000	158,676,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Savings Deposits [Member]
Deposits	103,025,000	98,635,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Money Market Deposits [Member]
Deposits	131,844,000	146,389,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Negotiable Order of Withdrawal (NOW) Accounts [Member]
Deposits	34,433,000	30,529,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Time Deposits [Member]
Deposits	232,326,000	210,882,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Interest Rate Swap [Member]
Interest rate swap receivable	791,000	1,187,000
Fair Value, Inputs, Level 3 [Member] \| Reported Value Measurement [Member]
Loans receivable, net	666,250,000	719,596,000
SBA servicing assets	327,000	316,000
Note payable	943,000	994,000
Fair Value, Inputs, Level 3 [Member] \| Estimate of Fair Value Measurement [Member]
Loans receivable, net	663,233,000	716,822,000
SBA servicing assets	391,000	375,000
Note payable	$ 916,000	$ 997,000

Fair value portion of the Federal Reserve Bank Stock.

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Fair value portion of interest receivable.

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Fair value of junior subordinated debt owned to unconsolidated trust.

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Fair value portion of investments classified as other.

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Represents the fair value of other real estate owned.

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Fair value portion of senior notes.

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Fair value portion of accrued expenses.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount 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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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

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

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

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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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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Fair value portion of notes payable.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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