Note 15 - Fair Value of Financial Instruments - Estimated Fair Value and Related Carrying or Notional Amounts of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Investment securities available-for-sale	$ 141,421	$ 153,871
Investment securities held-to-maturity	23,615	25,949
Reported Value Measurement [Member]
Cash and cash equivalents	41,798	27,124
Investment securities available-for-sale	141,421	153,871
Investment securities held-to-maturity	24,319	26,279
Federal funds sold	15,000	15,000
Federal Home Loan Bank stock	1,413	1,609
Loans, net of allowance for loan losses	355,529	346,121
Other liabilities - derivatives	977
Deposits	531,428	517,079
Short-term borrowings	10,366	15,594
Long-term debt	10,000	10,000
Federal funds sold	15,000	15,000
Other assets – derivatives		443
Deposits	531,428	517,079
Estimate of Fair Value Measurement [Member]
Cash and cash equivalents	41,798	27,124
Investment securities available-for-sale	141,421	153,871
Investment securities held-to-maturity	23,615	25,949
Federal funds sold	15,000	15,000
Federal Home Loan Bank stock	1,413	1,609
Loans, net of allowance for loan losses	0	342,248
Other liabilities - derivatives	977
Deposits	0	515,645
Short-term borrowings	10,366	15,594
Long-term debt	0	9,998
Federal funds sold	15,000	15,000
Other assets – derivatives		443
Deposits	0	515,645
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents	41,798	27,124
Investment securities available-for-sale
Investment securities held-to-maturity
Federal funds sold
Federal Home Loan Bank stock
Loans, net of allowance for loan losses
Other liabilities - derivatives
Deposits
Short-term borrowings
Long-term debt
Federal funds sold
Other assets – derivatives
Deposits
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents
Investment securities available-for-sale	141,421	153,871
Investment securities held-to-maturity	23,615	25,949
Federal funds sold	15,000	15,000
Federal Home Loan Bank stock
Loans, net of allowance for loan losses
Other liabilities - derivatives	977
Deposits	0	515,645
Short-term borrowings	10,366	15,594
Long-term debt	0	9,998
Federal funds sold	15,000	15,000
Other assets – derivatives		443
Deposits	0	515,645
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents
Investment securities available-for-sale
Investment securities held-to-maturity
Federal funds sold
Federal Home Loan Bank stock	1,413	1,609
Loans, net of allowance for loan losses	0	342,248
Other liabilities - derivatives
Deposits
Short-term borrowings
Long-term debt
Federal funds sold
Other assets – derivatives
Deposits

Fair value portion of federal funds sold.

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
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-Subparagraph (b)
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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.

+ References

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- Definition

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.

+ References

No definition available.

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 20
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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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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

No definition available.

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

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.

+ References

No definition available.

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- Definition

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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