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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans -Troubled Debt Restructurings (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($)	Jun. 30, 2015	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate Other [Member]
Number of contracts	2		2
Pre-modification outstanding principal balance	$ 3,008,000		$ 3,008
Post-modification outstanding principal balance	$ 3,008,000		$ 3,008
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member]
Number of contracts				1
Pre-modification outstanding principal balance				$ 994
Post-modification outstanding principal balance				$ 907
Number of contracts	2	0	2	1
Pre-modification outstanding principal balance	$ 3,008		$ 3,008	$ 994
Post-modification outstanding principal balance	$ 3,008		$ 3,008	$ 907

X

- Definition

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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- Definition

Post-modification amount of investment in financing receivables 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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- Definition

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+ 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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