Note 18 - Fair Value and Interest Rate Risk - Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Financial Assets:
Available-for-sale securities	$ 39,496	$ 25,576
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Financial Assets:
Available-for-sale securities	20,473	7,224
Corporate Debt Securities [Member]
Financial Assets:
Available-for-sale securities	12,974	13,804
Subordinated Notes [Member]
Financial Assets:
Available-for-sale securities	4,564	4,548
Reported Value Measurement [Member]
Financial Assets:
Financial assets, total	895,509	804,504
Financial Liabilities:
Financial liabilities, total	876,862	779,377
Estimate of Fair Value Measurement [Member]
Financial Assets:
Financial assets, total	885,323	793,970
Financial Liabilities:
Financial liabilities, total	875,279	777,850
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Brokered Deposits [Member]
Financial Liabilities:
Deposits	183,600	138,129
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Cash and Due from Banks [Member]
Financial Assets:
Cash and cash equivalents	7,381	3,582
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Interest-bearing Deposits [Member]
Financial Assets:
Cash and cash equivalents	59,056	45,147
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Brokered Deposits [Member]
Financial Liabilities:
Deposits	183,120	137,870
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Cash and Due from Banks [Member]
Financial Assets:
Cash and cash equivalents	7,381	3,582
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Interest-bearing Deposits [Member]
Financial Assets:
Cash and cash equivalents	59,056	45,147
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member]
Financial Assets:
Available-for-sale securities	1,485
Other investments	4,963	4,962
Federal Reserve Bank stock	2,866	2,502
Federal Home Loan Bank stock	4,928	5,889
Accrued interest receivable	3,766	3,496
Interest rate swap receivable	286
Financial Liabilities:
FHLB and correspondent bank borrowings	100,000	120,000
Senior notes	11,778	11,703
Subordinated debt	9,723
Junior subordinated debt owed to unconsolidated trust	8,094	8,086
Accrued interest payable	1,605	569
Interest rate swap liability	286
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Demand Deposits [Member]
Financial Liabilities:
Deposits	84,471	81,197
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Savings Deposits [Member]
Financial Liabilities:
Deposits	81,912	135,975
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Money Market Deposits [Member]
Financial Liabilities:
Deposits	85,197	16,575
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Negotiable Order of Withdrawal (NOW) Accounts [Member]
Financial Liabilities:
Deposits	26,100	25,476
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Time Deposits [Member]
Financial Liabilities:
Deposits	282,001	240,087
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Financial Assets:
Available-for-sale securities	20,473	7,224
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Corporate Debt Securities [Member]
Financial Assets:
Available-for-sale securities	12,974	13,804
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Subordinated Notes [Member]
Financial Assets:
Available-for-sale securities	4,564	4,548
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member]
Financial Assets:
Available-for-sale securities	1,485
Other investments	4,963	4,962
Federal Reserve Bank stock	2,866	2,502
Federal Home Loan Bank stock	4,928	5,889
Accrued interest receivable	3,766	3,496
Interest rate swap receivable	286
Financial Liabilities:
FHLB and correspondent bank borrowings	101,369	120,218
Senior notes	11,293	11,249
Subordinated debt	9,348
Junior subordinated debt owed to unconsolidated trust	8,094	8,086
Accrued interest payable	1,605	569
Interest rate swap liability	286
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Demand Deposits [Member]
Financial Liabilities:
Deposits	84,471	81,197
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Savings Deposits [Member]
Financial Liabilities:
Deposits	81,912	135,975
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Money Market Deposits [Member]
Financial Liabilities:
Deposits	85,197	16,575
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Negotiable Order of Withdrawal (NOW) Accounts [Member]
Financial Liabilities:
Deposits	26,100	25,476
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Time Deposits [Member]
Financial Liabilities:
Deposits	280,538	239,219
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Financial Assets:
Available-for-sale securities	20,473	7,224
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Corporate Debt Securities [Member]
Financial Assets:
Available-for-sale securities	12,974	13,804
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Subordinated Notes [Member]
Financial Assets:
Available-for-sale securities	4,564	4,548
Fair Value, Inputs, Level 3 [Member] \| Reported Value Measurement [Member]
Financial Assets:
Loans receivable, net	772,767	713,350
Financial Liabilities:
Note payable	1,388	1,580
Contingent consideration liability	707
Fair Value, Inputs, Level 3 [Member] \| Estimate of Fair Value Measurement [Member]
Financial Assets:
Loans receivable, net	762,581	702,816
Financial Liabilities:
Note payable	1,239	1,416
Contingent consideration liability	$ 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 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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