Note 13 - Fair Value and Interest Rate Risk - Financial Assets and Liabilities (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Fair value, total	$ 47,823,000	$ 48,317,000
SBA servicing assets	362,000
Reported Value Measurement [Member]
Financial assets, total	864,584,000	921,374,000
Financial liabilities, total	850,746,000	903,186,000
Estimate of Fair Value Measurement [Member]
Financial assets, total	854,620,000	914,414,000
Financial liabilities, total	860,323,000	907,534,000
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Brokered Deposits [Member]
Deposits	90,995,000	229,909,000
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Cash and Due from Banks [Member]
Cash and cash equivalents	3,231,000	2,693,000
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Interest-bearing Deposits [Member]
Cash and cash equivalents	46,405,000	36,711,000
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Brokered Deposits [Member]
Deposits	91,521,000	230,073,000
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Cash and Due from Banks [Member]
Cash and cash equivalents	3,231,000	2,693,000
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Interest-bearing Deposits [Member]
Cash and cash equivalents	46,405,000	36,711,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member]
Fair value, total	47,823,000	48,317,000
Other investments	4,450,000	4,450,000
Federal Reserve Bank stock	2,783,000	2,897,000
Federal Home Loan Bank stock	4,503,000	4,477,000
Loans held for sale	6,824,000	15,282,000
Accrued interest receivable	6,834,000	3,603,000
FHLB borrowings	90,000,000	100,000,000
Senior notes	11,909,000	11,853,000
Subordinated debt	9,774,000	9,752,000
Junior subordinated debt owed to unconsolidated trust	8,108,000	8,102,000
Accrued interest payable	1,091,000	1,971,000
Interest rate swap liability	1,303,000	694,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Demand Deposits [Member]
Deposits	161,871,000	88,135,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Savings Deposits [Member]
Deposits	91,169,000	64,020,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Money Market Deposits [Member]
Deposits	142,909,000	99,115,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Negotiable Order of Withdrawal (NOW) Accounts [Member]
Deposits	29,518,000	26,864,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Time Deposits [Member]
Deposits	210,969,000	261,492,000
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Interest Rate Swap [Member]
Interest rate swap receivable	1,303,000	694,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member]
Fair value, total	47,823,000	48,317,000
Other investments	4,450,000	4,450,000
Federal Reserve Bank stock	2,783,000	2,897,000
Federal Home Loan Bank stock	4,503,000	4,477,000
Loans held for sale	7,002,000	16,733,000
Accrued interest receivable	6,834,000	3,603,000
FHLB borrowings	97,786,000	103,962,000
Senior notes	12,033,000	11,722,000
Subordinated debt	10,145,000	9,747,000
Junior subordinated debt owed to unconsolidated trust	8,108,000	8,102,000
Accrued interest payable	1,091,000	1,971,000
Interest rate swap liability	1,303,000	694,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Demand Deposits [Member]
Deposits	161,871,000	88,135,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Savings Deposits [Member]
Deposits	91,169,000	64,020,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Money Market Deposits [Member]
Deposits	142,909,000	99,115,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Negotiable Order of Withdrawal (NOW) Accounts [Member]
Deposits	29,518,000	26,864,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Time Deposits [Member]
Deposits	211,724,000	261,914,000
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Interest Rate Swap [Member]
Interest rate swap receivable	1,303,000	694,000
Fair Value, Inputs, Level 3 [Member] \| Reported Value Measurement [Member]
Loans receivable, net	740,127,000	802,049,000
SBA servicing assets	301,000	201,000
Note payable	1,044,000	1,193,000
Contingent consideration liability	86,000	86,000
Fair Value, Inputs, Level 3 [Member] \| Estimate of Fair Value Measurement [Member]
Loans receivable, net	729,924,000	793,559,000
SBA servicing assets	362,000	280,000
Note payable	1,059,000	1,129,000
Contingent consideration liability	$ 86,000	$ 86,000

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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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 of contingent consideration in a business combination that is classified in shareholders' equity.

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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 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 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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