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Note 4 - Loans and Allowance for Loan Losses (Details) - Loans Modified as Troubled Debt Restructurings	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Originated Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	10	5
Pre-Modification Recorded Principal Balance	$ 2,022,000	$ 22,927,000
Post-Modification Recorded Principal Balance	$ 2,047,000	$ 23,027,000
Acquired Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	20	16
Pre-Modification Recorded Principal Balance	$ 2,262,000	$ 3,887,000
Post-Modification Recorded Principal Balance	$ 2,262,000	$ 3,887,000
Commercial Portfolio Segment [Member] | Originated Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	9	5
Pre-Modification Recorded Principal Balance	$ 1,876,000	$ 22,927,000
Post-Modification Recorded Principal Balance	$ 1,901,000	$ 23,027,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	9	2
Pre-Modification Recorded Principal Balance	$ 1,876,000	$ 5,994,000
Post-Modification Recorded Principal Balance	$ 1,901,000	$ 6,094,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	0
Pre-Modification Recorded Principal Balance	$ 0	$ 0
Post-Modification Recorded Principal Balance	$ 0	$ 0
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	2
Pre-Modification Recorded Principal Balance	$ 0	$ 16,787,000
Post-Modification Recorded Principal Balance	$ 0	$ 16,787,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	1
Pre-Modification Recorded Principal Balance	$ 0	$ 146,000
Post-Modification Recorded Principal Balance	$ 0	$ 146,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	0
Pre-Modification Recorded Principal Balance	$ 0	$ 0
Post-Modification Recorded Principal Balance	$ 0	$ 0
Commercial Portfolio Segment [Member] | Acquired Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	19	14
Pre-Modification Recorded Principal Balance	$ 2,119,000	$ 3,682,000
Post-Modification Recorded Principal Balance	$ 2,119,000	$ 3,682,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	3	7
Pre-Modification Recorded Principal Balance	$ 624,000	$ 1,604,000
Post-Modification Recorded Principal Balance	$ 624,000	$ 1,604,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	0
Pre-Modification Recorded Principal Balance	$ 0	$ 0
Post-Modification Recorded Principal Balance	$ 0	$ 0
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	7	2
Pre-Modification Recorded Principal Balance	$ 494,000	$ 1,619,000
Post-Modification Recorded Principal Balance	$ 494,000	$ 1,619,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	5	1
Pre-Modification Recorded Principal Balance	$ 714,000	$ 65,000
Post-Modification Recorded Principal Balance	$ 714,000	$ 65,000
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	4	4
Pre-Modification Recorded Principal Balance	$ 287,000	$ 394,000
Post-Modification Recorded Principal Balance	$ 287,000	$ 394,000
Retail Portfolio Segment [Member] | Originated Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	1	0
Pre-Modification Recorded Principal Balance	$ 146,000	$ 0
Post-Modification Recorded Principal Balance	$ 146,000	$ 0
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	1	0
Pre-Modification Recorded Principal Balance	$ 146,000	$ 0
Post-Modification Recorded Principal Balance	$ 146,000	$ 0
Retail Portfolio Segment [Member] | Originated Loan [Member] | 1-4 Family Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	0
Pre-Modification Recorded Principal Balance	$ 0	$ 0
Post-Modification Recorded Principal Balance	$ 0	$ 0
Retail Portfolio Segment [Member] | Acquired Loan [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	1	2
Pre-Modification Recorded Principal Balance	$ 143,000	$ 205,000
Post-Modification Recorded Principal Balance	$ 143,000	$ 205,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	1
Pre-Modification Recorded Principal Balance	$ 0	$ 26,000
Post-Modification Recorded Principal Balance	$ 0	$ 26,000
Retail Portfolio Segment [Member] | Acquired Loan [Member] | 1-4 Family Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	1	1
Pre-Modification Recorded Principal Balance	$ 143,000	$ 179,000
Post-Modification Recorded Principal Balance	$ 143,000	$ 179,000

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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
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