Note 10 - Fair Value and Interest Rate Risk - Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financial Assets:
Available-for-sale securities, at fair value	$ 24,793	$ 25,576
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Financial Assets:
Available-for-sale securities, at fair value	6,655	7,224
Corporate Debt Securities [Member]
Financial Assets:
Available-for-sale securities, at fair value	13,601	13,804
Subordinated Notes [Member]
Financial Assets:
Available-for-sale securities, at fair value	4,537	4,548
Reported Value Measurement [Member]
Financial Assets:
Financial assets, total	821,225	804,504
Financial Liabilities:
Financial liabilities, total	797,594	779,377
Estimate of Fair Value Measurement [Member]
Financial Assets:
Financial assets, total	809,146	793,970
Financial Liabilities:
Financial liabilities, total	794,891	777,850
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Brokered Deposits [Member]
Financial Liabilities:
Deposits	165,190	138,129
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Cash and Due from Banks [Member]
Financial Assets:
Cash and cash equivalents	3,865	3,582
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Interest-bearing Deposits [Member]
Financial Assets:
Cash and cash equivalents	58,127	45,659
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Brokered Deposits [Member]
Financial Liabilities:
Deposits	164,650	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	3,865	3,582
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Interest-bearing Deposits [Member]
Financial Assets:
Cash and cash equivalents	58,127	45,659
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member]
Financial Assets:
Other investments	4,450	4,450
Federal Reserve Bank stock	2,526	2,502
Federal Home Loan Bank stock	5,889	5,889
Accrued interest receivable	3,505	3,496
Financial Liabilities:
FHLB and correspondent bank borrowings	120,000	120,000
Senior notes	11,722	11,703
Subordinated debentures	8,088	8,086
Accrued interest payable	954	569
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Demand Deposits [Member]
Financial Liabilities:
Deposits	71,736	81,197
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Savings Deposits [Member]
Financial Liabilities:
Deposits	132,118	135,975
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Money Market Deposits [Member]
Financial Liabilities:
Deposits	11,936	16,575
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Negotiable Order of Withdrawal (NOW) Accounts [Member]
Financial Liabilities:
Deposits	23,461	25,476
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Time Deposits [Member]
Financial Liabilities:
Deposits	250,857	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, at fair value	6,655	7,224
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Corporate Debt Securities [Member]
Financial Assets:
Available-for-sale securities, at fair value	13,601	13,804
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Subordinated Notes [Member]
Financial Assets:
Available-for-sale securities, at fair value	4,537	4,548
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member]
Financial Assets:
Other investments	4,450	4,450
Federal Reserve Bank stock	2,526	2,502
Federal Home Loan Bank stock	5,889	5,889
Accrued interest receivable	3,505	3,496
Financial Liabilities:
FHLB and correspondent bank borrowings	120,086	120,218
Senior notes	11,116	11,249
Subordinated debentures	8,088	8,086
Accrued interest payable	954	569
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Demand Deposits [Member]
Financial Liabilities:
Deposits	71,736	81,197
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Savings Deposits [Member]
Financial Liabilities:
Deposits	132,118	135,975
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Money Market Deposits [Member]
Financial Liabilities:
Deposits	11,936	16,575
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Negotiable Order of Withdrawal (NOW) Accounts [Member]
Financial Liabilities:
Deposits	23,461	25,476
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Time Deposits [Member]
Financial Liabilities:
Deposits	249,401	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, at fair value	6,655	7,224
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Corporate Debt Securities [Member]
Financial Assets:
Available-for-sale securities, at fair value	13,601	13,804
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Subordinated Notes [Member]
Financial Assets:
Available-for-sale securities, at fair value	4,537	4,548
Fair Value, Inputs, Level 3 [Member] \| Reported Value Measurement [Member]
Financial Assets:
Loans receivable, net	718,070	713,350
Financial Liabilities:
Note payable	1,532	1,580
Fair Value, Inputs, Level 3 [Member] \| Estimate of Fair Value Measurement [Member]
Financial Assets:
Loans receivable, net	705,991	702,816
Financial Liabilities:
Note payable	$ 1,345	$ 1,416

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 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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-SubTopic 10
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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 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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