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Note 3 - Loans and Allowance for Loan Losses - Loans Modified as Troubled Debt Restructurings (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member]
Number of Contracts	0	4	1	10
Pre- Modification Recorded Principal Balance	$ 0	$ 1,308,000	$ 20,000	$ 1,876,000
Post- Modification Recorded Principal Balance	$ 0	$ 1,308,000	$ 20,000	$ 1,901,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Number of Contracts	0	0	0	0
Pre- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Post- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member]
Number of Contracts	1	0	1	0
Pre- Modification Recorded Principal Balance	$ 167,000	$ 0	$ 167,000	$ 0
Post- Modification Recorded Principal Balance	$ 167,000	$ 0	$ 167,000	$ 0
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member]
Number of Contracts	0	0	0	0
Pre- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Post- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residentia lRental Loan [Member]
Number of Contracts	0	0	0	0
Pre- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Post- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Commercial Portfolio Segment [Member] | Originated Loan [Member]
Number of Contracts	1	4	2	10
Pre- Modification Recorded Principal Balance	$ 167,000	$ 1,308,000	$ 187,000	$ 1,876,000
Post- Modification Recorded Principal Balance	$ 167,000	$ 1,308,000	$ 187,000	$ 1,901,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member]
Number of Contracts	0	2	0	2
Pre- Modification Recorded Principal Balance	$ 0	$ 286,000	$ 0	$ 286,000
Post- Modification Recorded Principal Balance	$ 0	$ 286,000	$ 0	$ 286,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Number of Contracts	0	0	0	0
Pre- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Post- Modification Recorded Principal Balance	$ 0	$ 0	$ 0	$ 0
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member]
Number of Contracts	0	3	0	5
Pre- Modification Recorded Principal Balance	$ 0	$ 119,000	$ 0	$ 169,000
Post- Modification Recorded Principal Balance	$ 0	$ 119,000	$ 0	$ 169,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member]
Number of Contracts	1	1	1	1
Pre- Modification Recorded Principal Balance	$ 60,000	$ 302,000	$ 60,000	$ 302,000
Post- Modification Recorded Principal Balance	$ 60,000	$ 302,000	$ 60,000	$ 302,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residentia lRental Loan [Member]
Number of Contracts	1	3	1	3
Pre- Modification Recorded Principal Balance	$ 7,000	$ 265,000	$ 7,000	$ 265,000
Post- Modification Recorded Principal Balance	$ 7,000	$ 265,000	$ 7,000	$ 265,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member]
Number of Contracts	2	9	2	11
Pre- Modification Recorded Principal Balance	$ 67,000	$ 972,000	$ 67,000	$ 1,022,000
Post- Modification Recorded Principal Balance	$ 67,000	$ 972,000	$ 67,000	$ 1,022,000
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member]
Number of Contracts	2	0	2	0
Pre- Modification Recorded Principal Balance	$ 184,000	$ 0	$ 184,000	$ 0
Post- Modification Recorded Principal Balance	$ 184,000	$ 0	$ 184,000	$ 0
Retail Portfolio Segment [Member] | Originated Loan [Member] | One to Four Family Mortgages [Member]
Number of Contracts	1	0	1	0
Pre- Modification Recorded Principal Balance	$ 33,000	$ 0	$ 33,000	$ 0
Post- Modification Recorded Principal Balance	$ 40,000	$ 0	$ 40,000	$ 0
Retail Portfolio Segment [Member] | Originated Loan [Member]
Number of Contracts	3	0	3	0
Pre- Modification Recorded Principal Balance	$ 217,000	$ 0	$ 217,000	$ 0
Post- Modification Recorded Principal Balance	$ 224,000	$ 0	$ 224,000	$ 0
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member]
Number of Contracts	1	1	2	1
Pre- Modification Recorded Principal Balance	$ 25,000	$ 161,000	$ 51,000	$ 161,000
Post- Modification Recorded Principal Balance	$ 25,000	$ 161,000	$ 51,000	$ 161,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] | One to Four Family Mortgages [Member]
Number of Contracts	0	0	1	0
Pre- Modification Recorded Principal Balance	$ 0	$ 0	$ 19,000	$ 0
Post- Modification Recorded Principal Balance	$ 0	$ 0	$ 19,000	$ 0
Retail Portfolio Segment [Member] | Acquired Loan [Member]
Number of Contracts	1	1	3	1
Pre- Modification Recorded Principal Balance	$ 25,000	$ 161,000	$ 70,000	$ 161,000
Post- Modification Recorded Principal Balance	$ 25,000	$ 161,000	$ 70,000	$ 161,000
Originated Loan [Member]
Number of Contracts	4	4	5	10
Pre- Modification Recorded Principal Balance	$ 384,000	$ 1,308,000	$ 404,000	$ 1,876,000
Post- Modification Recorded Principal Balance	$ 391,000	$ 1,308,000	$ 411,000	$ 1,901,000
Acquired Loan [Member]
Number of Contracts	3	10	5	12
Pre- Modification Recorded Principal Balance	$ 92,000	$ 1,133,000	$ 137,000	$ 1,183,000
Post- Modification Recorded Principal Balance	$ 92,000	$ 1,133,000	$ 137,000	$ 1,183,000

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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+ 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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+ References

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-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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