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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details Textual)	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2016 USD ($)	Jun. 30, 2016	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Nonperforming Financial Instruments [Member]
Interest and Fee Income, Loans and Leases				$ 0	$ 0	$ 0
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member] | Forgive Principal, Reduce Interest Rate, Capitalize Interest, and Re-amortize Payments [Member]
Allowance for Credit Losses, Change in Method of Calculating Impairment	$ 0			$ 0
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Financing Receivable, Modifications, Number of Contracts		2		2
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] | Forgive Principal, Reduce Interest Rate, Capitalize Interest, and Re-amortize Payments [Member]
Financing Receivable Modifications Principal Forgiven					$ 100,000
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member]
Financing Receivable, Modifications, Number of Contracts					1
Commercial Non Real Estate Segment [Member] | Commercial and Industrial [Member]
Financing Receivable, Modifications, Number of Contracts	1			1
Consumer Non Real Estate Portfolio Segment [Member] | Automobile Loan [Member]
Financing Receivable, Modifications, Number of Contracts	1			1
Special Mention [Member]
Increase in Percentage of Allocation Loans Rated Special Mention				50.00%
Classified Excluding Impaired [Member]
Increase in Percentage of Allocation Loans Rated Classified				100.00%
Interest and Fee Income, Loans and Leases	$ 7,409,000		$ 7,676,000	$ 22,032,000	$ 22,886,000
Financing Receivable, Reclassification to Held-for-sale				0
Transfer of Loans Held-for-sale to Portfolio Loans				$ 0
Financing Receivable, Modifications, Number of Contracts	2		0	4	1
Financing Receivable, Modifications, Subsequent Default, Number of Contracts				0	0
Threshold for Designation to Impaired Status				$ 250,000
Threshold Period for Considering Loans as Special Mention or Classified				75 days
Financing Receivable, Modifications, Recorded Investment	$ 8,563,000		$ 11,861,000	$ 8,563,000	$ 11,861,000	$ 13,453,000

X

- Definition

Amount of principal forgiven in a troubled debt restructuring agreement.

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Amount of allowance for credit losses related to receivables which had been measured under a general allowance for credit losses methodology that are now identified as troubled debt restructurings.

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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.

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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.

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The amount of financing receivables reclassified to held for sale during the reporting period.

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The aggregate interest and fee income generated by: (1) loans the Entity has positive intent and ability to hold for the foreseeable future, or until maturity or payoff, including commercial and consumer loans, whether domestic or foreign, which may consist of: (a) industrial and agricultural; (b) real estate; and (c) real estate construction loans; (d) trade financing; (e) lease financing; (f) home equity lines-of-credit; (g) automobile and other vehicle loans; and (h) credit card and other revolving-type loans and (2) loans and leases held-for-sale which may include mortgage loans, direct financing, and sales-type leases.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.1)
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Value of loans held-for-sale transferred to loans held in the entity's portfolio in noncash transactions.

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