Note 17 - Fair Value and Interest Rate Risk - Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Financial Assets:
Available-for-sale securities	$ 25,576	$ 24,428
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Financial Assets:
Available-for-sale securities	7,224	10,441
Corporate Debt Securities [Member]
Financial Assets:
Available-for-sale securities	13,804	8,961
Subordinated Notes [Member]
Financial Assets:
Available-for-sale securities	4,548	5,026
Reported Value Measurement [Member]
Financial Assets:
Financial assets, total	804,504	708,593
Financial Liabilities:
Financial liabilities, total	779,377	688,918
Estimate of Fair Value Measurement [Member]
Financial Assets:
Financial assets, total	793,970	708,368
Financial Liabilities:
Financial liabilities, total	777,850	687,463
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Brokered Deposits [Member]
Financial Liabilities:
Deposits	138,129	63,932
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Cash and Due from Banks [Member]
Financial Assets:
Cash and cash equivalents	3,607	2,596
Fair Value, Inputs, Level 1 [Member] \| Reported Value Measurement [Member] \| Interest-bearing Deposits [Member]
Financial Assets:
Cash and cash equivalents	45,634	89,693
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Brokered Deposits [Member]
Financial Liabilities:
Deposits	137,870	63,897
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Cash and Due from Banks [Member]
Financial Assets:
Cash and cash equivalents	3,607	2,596
Fair Value, Inputs, Level 1 [Member] \| Estimate of Fair Value Measurement [Member] \| Interest-bearing Deposits [Member]
Financial Assets:
Cash and cash equivalents	45,634	89,693
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member]
Financial Assets:
Other investments	4,450	4,450
Federal Reserve Bank stock	2,502	2,109
Federal Home Loan Bank stock	5,889	5,609
Accrued interest receivable	3,496	2,726
Financial Liabilities:
FHLB and correspondent bank borrowings	120,000	138,000
Senior notes	11,703	11,628
Subordinated debentures	8,086	8,079
Accrued interest payable	569	118
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Demand Deposits [Member]
Financial Liabilities:
Deposits	81,197	76,772
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Savings Deposits [Member]
Financial Liabilities:
Deposits	135,975	131,429
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Money Market Deposits [Member]
Financial Liabilities:
Deposits	16,575	15,593
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Negotiable Order of Withdrawal (NOW) Accounts [Member]
Financial Liabilities:
Deposits	25,476	29,912
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Time Deposits [Member]
Financial Liabilities:
Deposits	240,087	211,686
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	7,224	10,441
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Corporate Debt Securities [Member]
Financial Assets:
Available-for-sale securities	13,804	8,961
Fair Value, Inputs, Level 2 [Member] \| Reported Value Measurement [Member] \| Subordinated Notes [Member]
Financial Assets:
Available-for-sale securities	2,528	3,026
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member]
Financial Assets:
Other investments	4,450	4,450
Federal Reserve Bank stock	2,502	2,109
Federal Home Loan Bank stock	5,889	5,609
Accrued interest receivable	3,496	2,726
Financial Liabilities:
FHLB and correspondent bank borrowings	120,218	138,149
Senior notes	11,249	11,628
Subordinated debentures	8,086	8,079
Accrued interest payable	569	118
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Demand Deposits [Member]
Financial Liabilities:
Deposits	81,197	76,772
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Savings Deposits [Member]
Financial Liabilities:
Deposits	135,975	131,429
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Money Market Deposits [Member]
Financial Liabilities:
Deposits	16,575	15,593
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Negotiable Order of Withdrawal (NOW) Accounts [Member]
Financial Liabilities:
Deposits	25,476	29,912
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Time Deposits [Member]
Financial Liabilities:
Deposits	239,219	210,321
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	7,224	10,441
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Corporate Debt Securities [Member]
Financial Assets:
Available-for-sale securities	13,804	8,961
Fair Value, Inputs, Level 2 [Member] \| Estimate of Fair Value Measurement [Member] \| Subordinated Notes [Member]
Financial Assets:
Available-for-sale securities	2,528	3,026
Fair Value, Inputs, Level 3 [Member] \| Reported Value Measurement [Member]
Financial Assets:
Loans receivable, net	713,350	576,982
Financial Liabilities:
Note payable	1,580	1,769
Fair Value, Inputs, Level 3 [Member] \| Reported Value Measurement [Member] \| Subordinated Notes [Member]
Financial Assets:
Available-for-sale securities	2,020	2,000
Fair Value, Inputs, Level 3 [Member] \| Estimate of Fair Value Measurement [Member]
Financial Assets:
Loans receivable, net	702,816	576,757
Financial Liabilities:
Note payable	1,416	1,565
Fair Value, Inputs, Level 3 [Member] \| Estimate of Fair Value Measurement [Member] \| Subordinated Notes [Member]
Financial Assets:
Available-for-sale securities	$ 2,020	$ 2,000

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 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 and equity securities categorized neither as held-to-maturity nor trading.

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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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