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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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