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Note 4 - Loans and Allowance for Loan Losses (Details) - Components of Loan Portfolio - USD ($) | 6 Months Ended |  |
--- | --- | --- | ---
Jun. 30, 2015 | Dec. 31, 2014 | Jun. 30, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 2,171,832,000 | $ 2,089,277,000 |
Loans, percentage of portfolio | 100.00% | 100.00% |
Loans, percentage of change in loans | 4.00% |  |
Originated Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 1,429,623,000 | $ 1,246,116,000 | $ 1,145,097,000
Loans, percentage of portfolio | 100.00% | 100.00% |
Loans, percentage of change in loans | 14.70% |  |
Acquired Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 742,209,000 | $ 843,161,000 |
Loans, percentage of portfolio | 100.00% | 100.00% |
Loans, percentage of change in loans | (12.00%) |  |
Commercial Portfolio Segment [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 1,820,431,000 | $ 1,715,303,000 |
Loans, percentage of portfolio | 83.80% | 82.10% |
Loans, percentage of change in loans | 6.10% |  |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 622,073,000 | $ 550,607,000 |
Loans, percentage of portfolio | 28.70% | 26.40% |
Loans, percentage of change in loans | 13.00% |  |
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 47,622,000 | $ 51,974,000 |
Loans, percentage of portfolio | 2.20% | 2.50% |
Loans, percentage of change in loans | (8.40%) |  |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 422,354,000 | $ 430,388,000 |
Loans, percentage of portfolio | 19.40% | 20.50% |
Loans, percentage of change in loans | (1.90%) |  |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 603,724,000 | $ 559,574,000 |
Loans, percentage of portfolio | 27.80% | 26.80% |
Loans, percentage of change in loans | 7.90% |  |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 124,658,000 | $ 122,760,000 |
Loans, percentage of portfolio | 5.70% | 5.90% |
Loans, percentage of change in loans | 1.50% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 1,322,388,000 | $ 1,153,189,000 | 1,076,609,000
Loans, percentage of portfolio | 92.50% | 92.50% |
Loans, percentage of change in loans | 14.70% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 487,440,000 | $ 384,570,000 |
Loans, percentage of portfolio | 34.10% | 30.80% |
Loans, percentage of change in loans | 26.70% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 28,853,000 | $ 29,826,000 |
Loans, percentage of portfolio | 2.00% | 2.40% |
Loans, percentage of change in loans | (3.30%) |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 297,694,000 | $ 291,758,000 |
Loans, percentage of portfolio | 20.80% | 23.40% |
Loans, percentage of change in loans | 2.00% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 469,433,000 | $ 410,977,000 |
Loans, percentage of portfolio | 32.90% | 33.00% |
Loans, percentage of change in loans | 14.20% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Retail Portfolio Segment [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 38,968,000 | $ 36,058,000 |
Loans, percentage of portfolio | 2.70% | 2.90% |
Loans, percentage of change in loans | 8.10% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 38,968,000 | $ 36,058,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 498,043,000 | $ 562,114,000 |
Loans, percentage of portfolio | 67.10% | 66.60% |
Loans, percentage of change in loans | (11.40%) |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 134,633,000 | $ 166,037,000 |
Loans, percentage of portfolio | 18.10% | 19.70% |
Loans, percentage of change in loans | (18.90%) |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 18,769,000 | $ 22,148,000 |
Loans, percentage of portfolio | 2.50% | 2.60% |
Loans, percentage of change in loans | (15.30%) |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 124,660,000 | $ 138,630,000 |
Loans, percentage of portfolio | 16.80% | 16.40% |
Loans, percentage of change in loans | (10.10%) |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 134,291,000 | $ 148,597,000 |
Loans, percentage of portfolio | 18.10% | 17.60% |
Loans, percentage of change in loans | (9.60%) |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 85,690,000 | $ 86,702,000 |
Loans, percentage of portfolio | 11.60% | 10.30% |
Loans, percentage of change in loans | (1.20%) |  |
Retail Portfolio Segment [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 351,401,000 | $ 373,974,000 |
Loans, percentage of portfolio | 16.20% | 17.90% |
Loans, percentage of change in loans | (6.00%) |  |
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 149,494,000 | $ 159,278,000 |
Loans, percentage of portfolio | 6.90% | 7.60% |
Loans, percentage of change in loans | (6.10%) |  |
Retail Portfolio Segment [Member] | 1-4 Family Mortgages [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 201,907,000 | $ 214,696,000 |
Loans, percentage of portfolio | 9.30% | 10.30% |
Loans, percentage of change in loans | (6.00%) |  |
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 107,235,000 | $ 92,927,000 | $ 68,488,000
Loans, percentage of portfolio | 7.50% | 7.50% |
Loans, percentage of change in loans | 15.40% |  |
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 60,417,000 | $ 50,059,000 |
Loans, percentage of portfolio | 4.20% | 4.00% |
Loans, percentage of change in loans | 20.70% |  |
Retail Portfolio Segment [Member] | Originated Loan [Member] | 1-4 Family Mortgages [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 46,818,000 | $ 42,868,000 |
Loans, percentage of portfolio | 3.30% | 3.50% |
Loans, percentage of change in loans | 9.20% |  |
Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 244,166,000 | $ 281,047,000 |
Loans, percentage of portfolio | 32.90% | 33.40% |
Loans, percentage of change in loans | (13.10%) |  |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 89,077,000 | $ 109,219,000 |
Loans, percentage of portfolio | 12.00% | 13.00% |
Loans, percentage of change in loans | (18.40%) |  |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | 1-4 Family Mortgages [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 155,089,000 | $ 171,828,000 |
Loans, percentage of portfolio | 20.90% | 20.40% |
Loans, percentage of change in loans | (9.70%) |  |

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