Note 11 - Fair Value and Interest Rate Risk - Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Fair value, total	$ 40,275	$ 39,496
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Fair value, total	19,976	20,473
Corporate Debt Securities [Member]
Fair value, total	12,828	12,974
Subordinated Notes [Member]
Fair value, total	5,980	4,564
Reported Value Measurement [Member]
Financial assets, total	894,026	895,509
Financial liabilities, total	876,140	876,862
Estimate of Fair Value Measurement [Member]
Financial assets, total	884,836	885,323
Financial liabilities, total	877,544	875,279
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Brokered Deposits [Member]
Deposits	182,794	183,600
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Cash and Due from Banks [Member]
Cash and cash equivalents	6,661	7,381
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Interest-bearing Deposits [Member]
Cash and cash equivalents	49,971	59,056
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Brokered Deposits [Member]
Deposits	182,804	183,120
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Cash and Due from Banks [Member]
Cash and cash equivalents	6,661	7,381
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Interest-bearing Deposits [Member]
Cash and cash equivalents	49,971	59,056
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member]
Fair value, total	1,491	1,485
Other investments	4,963	4,963
Federal Reserve Bank stock	2,892	2,866
Federal Home Loan Bank stock	4,513	4,928
Accrued interest receivable	3,621	3,766
Interest swap receivable	417	286
FHLB borrowings	90,000	100,000
Senior notes	11,796	11,778
Subordinated debt	9,731	9,723
Junior subordinated debt owed to unconsolidated trust	8,096	8,094
Accrued interest payable	1,854	1,605
Interest swap liability	417	286
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Demand Deposits [Member]
Deposits	82,248	84,471
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Savings Deposits [Member]
Deposits	67,708	81,912
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Money Market Deposits [Member]
Deposits	88,493	85,197
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Negotiable Order of Withdrawal (NOW) Accounts [Member]
Deposits	24,924	26,100
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Time Deposits [Member]
Deposits	306,654	282,001
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Fair value, total	19,976	20,473
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Corporate Debt Securities [Member]
Fair value, total	12,828	12,974
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Subordinated Notes [Member]
Fair value, total	5,980	4,564
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member]
Fair value, total	1,491	1,485
Other investments	4,963	4,963
Federal Reserve Bank stock	2,892	2,866
Federal Home Loan Bank stock	4,513	4,928
Accrued interest receivable	3,621	3,766
Interest swap receivable	417	286
FHLB borrowings	92,509	101,369
Senior notes	11,433	11,293
Subordinated debt	9,490	9,348
Junior subordinated debt owed to unconsolidated trust	8,096	8,094
Accrued interest payable	1,854	1,605
Interest swap liability	417	286
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Demand Deposits [Member]
Deposits	82,248	84,471
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Savings Deposits [Member]
Deposits	67,708	81,912
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Money Market Deposits [Member]
Deposits	88,493	85,197
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Negotiable Order of Withdrawal (NOW) Accounts [Member]
Deposits	24,924	26,100
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Time Deposits [Member]
Deposits	306,260	280,538
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Fair value, total	19,976	20,473
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Corporate Debt Securities [Member]
Fair value, total	12,828	12,974
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Subordinated Notes [Member]
Fair value, total	5,980	4,564
Fair Value, Inputs, Level 3 [Member] \| Reported Value Measurement [Member]
Loans receivable, net	780,713	772,767
Note payable	1,339	1,388
Contingent consideration liability	86	707
Fair Value, Inputs, Level 3 [Member] \| Estimate of Fair Value Measurement [Member]
Loans receivable, net	771,523	762,581
Note payable	1,222	1,239
Contingent consideration liability	$ 86	$ 707

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, after the effects of master netting arrangements, of a financial liability or 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 liabilities 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 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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