Note 15 - Fair Value of Financial Instruments - Estimated Fair Value and Related Carrying or Notional Amounts of Company's Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Assets:
Investment securities available-for-sale	$ 158,425	$ 181,910
Investment securities held-to-maturity	27,303	25,508
Reported Value Measurement [Member]
Assets:
Cash and cash equivalents	32,554	23,530
Investment securities available-for-sale	158,425	181,910
Investment securities held-to-maturity	27,377	25,904
Federal Home Loan Bank stock	1,396	1,581
Loans, net of allowance for loan losses	338,026	322,772
Other assets - derivatives	291	346
Liabilities:
Deposits	508,385	497,556
Short-term borrowings	10,635	10,119
Long-term debt	10,000	15,000
Deposits	508,385	497,556
Estimate of Fair Value Measurement [Member]
Assets:
Cash and cash equivalents	32,554	23,530
Investment securities available-for-sale	158,425	181,910
Investment securities held-to-maturity	27,303	25,508
Federal Home Loan Bank stock	1,396	1,581
Loans, net of allowance for loan losses	327,251	319,881
Other assets - derivatives	291	346
Liabilities:
Deposits	507,298	497,037
Short-term borrowings	10,634	10,119
Long-term debt	10,000	14,998
Deposits	507,298	497,037
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Assets:
Cash and cash equivalents	32,554	23,530
Investment securities available-for-sale
Investment securities held-to-maturity
Federal Home Loan Bank stock
Loans, net of allowance for loan losses
Other assets - derivatives
Liabilities:
Deposits
Short-term borrowings
Long-term debt
Deposits
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Assets:
Cash and cash equivalents
Investment securities available-for-sale	158,425	181,910
Investment securities held-to-maturity	27,303	25,508
Federal Home Loan Bank stock
Loans, net of allowance for loan losses
Other assets - derivatives	291	346
Liabilities:
Deposits	507,298	497,037
Short-term borrowings	10,634	10,119
Long-term debt	10,000	14,998
Deposits	507,298	497,037
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Assets:
Cash and cash equivalents
Investment securities available-for-sale
Investment securities held-to-maturity
Federal Home Loan Bank stock	1,396	1,581
Loans, net of allowance for loan losses	327,251	319,881
Other assets - derivatives
Liabilities:
Deposits
Short-term borrowings
Long-term debt
Deposits

Amount of debt securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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, 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.

+ References

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- References

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- Definition

Fair value of investments in debt securities classified as held-to-maturity.

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- Definition

Fair value portion of investments in Federal Home Loan Bank (FHLBank) stock.

+ References

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- Definition

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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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

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