Note 18 - Fair Value Disclosure Measurements - Estimated Fair Value of the Company's Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Financial assets:
Investment securities available for sale	$ 95,283	$ 114,376
Reported Value Measurement [Member]
Financial assets:
Cash and cash equivalents	39,886	32,495
Investment securities available for sale	95,283	114,376
Loans held for sale	463	634
Net loans	916,023	602,542
Bank-owned life insurance	15,652	13,540
Federal Home Loan Bank stock	3,589	2,204
Accrued interest receivable	3,288	2,426
Financial liabilities:
Deposits	878,194	629,934
Short-term borrowings	74,707	68,359
Other borrowings	29,065	9,437
Accrued interest payable	578	395
Estimate of Fair Value Measurement [Member]
Financial assets:
Cash and cash equivalents	39,886	32,495
Investment securities available for sale	95,283	114,376
Loans held for sale	463	634
Net loans	913,323	604,447
Bank-owned life insurance	15,652	13,540
Federal Home Loan Bank stock	3,589	2,204
Accrued interest receivable	3,288	2,426
Financial liabilities:
Deposits	877,227	630,371
Short-term borrowings	74,707	68,359
Other borrowings	29,069	9,512
Accrued interest payable	578	395
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 1 [Member]
Financial assets:
Cash and cash equivalents	39,886	32,495
Investment securities available for sale
Loans held for sale
Net loans
Bank-owned life insurance	15,652	13,540
Federal Home Loan Bank stock	3,589	2,204
Accrued interest receivable	3,288	2,426
Financial liabilities:
Deposits	635,207	440,500
Short-term borrowings	74,707	68,359
Other borrowings
Accrued interest payable	578	395
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 2 [Member]
Financial assets:
Cash and cash equivalents
Investment securities available for sale	95,283	114,376
Loans held for sale	463	634
Net loans
Bank-owned life insurance
Federal Home Loan Bank stock
Accrued interest receivable
Financial liabilities:
Deposits
Short-term borrowings
Other borrowings
Accrued interest payable
Estimate of Fair Value Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Financial assets:
Cash and cash equivalents
Investment securities available for sale
Loans held for sale
Net loans	913,323	604,447
Bank-owned life insurance
Federal Home Loan Bank stock
Accrued interest receivable
Financial liabilities:
Deposits	242,020	189,871
Short-term borrowings
Other borrowings	29,069	9,512
Accrued interest payable

Fair value portion of accrued interest payable.

No definition available.

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- Definition

The fair value portion of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

+ References

No definition available.

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- Definition

The fair value portion as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

+ References

No definition available.

+ Details

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

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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

No definition available.

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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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- References

No definition available.

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- References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75030709&loc=d3e39828-111592

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI http://asc.fasb.org/subtopic&trid=2196772

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- Definition

Fair value portion of other liabilities.

+ References

No definition available.

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Period Type:	instant

- 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.

+ References

No definition available.

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