Note 7 - Loans & Allowance for Loan Losses (Details Textual)	3 Months Ended
Mar. 31, 2017 USD ($) contract loan	Mar. 31, 2016 USD ($) contract	Dec. 31, 2016 USD ($)
Accounts Notes And Loans Receivable [Line Items]
Bank Overdrafts	$ 118,000		$ 171,000
Financing Receivable, Modifications, Recorded Investment	$ 4,956,000		5,374,000
Number of TDRs \| contract	0	9
Loans and Leases Receivable, Impaired, Commitment to Lend	$ 925,000		30,000
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$ 3,000	$ 0
Financing Receivable, Modifications, Subsequent Default, Number of Contracts \| contract	0	0
Consumer Mortgage Loan on Real Estate Number of Loan in Foreclosure \| loan	3
Performing Financial Instruments [Member]
Accounts Notes And Loans Receivable [Line Items]
Financing Receivable, Modifications, Recorded Investment	$ 1,425,000		1,819,000
Nonperforming Financial Instruments [Member]
Accounts Notes And Loans Receivable [Line Items]
Financing Receivable, Modifications, Recorded Investment	3,531,000		$ 3,555,000
Residential Portfolio Segment [Member]
Accounts Notes And Loans Receivable [Line Items]
Consumer Mortgage Loans in Process of Foreclosure, Amount	$ 516,000
Residential Portfolio Segment [Member] \| Maximum [Member]
Accounts Notes And Loans Receivable [Line Items]
Loan to Value Ratio	80.00%

Consumer mortgage loan on real estate number of loan in foreclosure.

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The ratio of the amount of mortgage to the underlying collateral.

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Carrying value as of the balance sheet date of payments made in excess of existing cash balances, which will be honored by the bank but reflected as a loan to the entity. Overdrafts generally have a very short time frame for correction or repayment and are therefore more similar to short-term bank financing than trade financing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Current Liabilities
-URI http://asc.fasb.org/extlink&oid=6509677

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

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Reflects the amount of the write-down related to a troubled debt restructuring.

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- Definition

Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

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