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Note 3 - Loans and Allowance for Loan Losses (Details) - Components of Loan Portfolio - USD ($) | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2015 | Dec. 31, 2014 | Sep. 30, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 2,217,388,000 | $ 2,089,277,000 |
Loans, percentage of portfolio | 100.00% | 100.00% |
Loans, percentage of change in loans | 6.10% |  |
Originated Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 1,519,710,000 | $ 1,246,116,000 | $ 1,186,713,000
Loans, percentage of portfolio | 100.00% | 100.00% |
Loans, percentage of change in loans | 22.00% |  |
Acquired Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 697,678,000 | $ 843,161,000 |
Loans, percentage of portfolio | 100.00% | 100.00% |
Loans, percentage of change in loans | (17.30%) |  |
Commercial Portfolio Segment [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 1,877,620,000 | $ 1,715,303,000 |
Loans, percentage of portfolio | 84.70% | 82.10% |
Loans, percentage of change in loans | 9.50% |  |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 643,118,000 | $ 550,607,000 |
Loans, percentage of portfolio | 29.00% | 26.40% |
Loans, percentage of change in loans | 16.80% |  |
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) | $ 47,734,000 | $ 51,974,000 |
Loans, percentage of portfolio | 2.20% | 2.50% |
Loans, percentage of change in loans | (8.20%) |  |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 427,016,000 | $ 430,388,000 |
Loans, percentage of portfolio | 19.30% | 20.50% |
Loans, percentage of change in loans | (0.80%) |  |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 636,227,000 | $ 559,574,000 |
Loans, percentage of portfolio | 28.60% | 26.80% |
Loans, percentage of change in loans | 13.70% |  |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 123,525,000 | $ 122,760,000 |
Loans, percentage of portfolio | 5.60% | 5.90% |
Loans, percentage of change in loans | 0.60% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 1,402,320,000 | $ 1,153,189,000 | 1,103,802,000
Loans, percentage of portfolio | 92.30% | 92.50% |
Loans, percentage of change in loans | 21.60% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 522,346,000 | $ 384,570,000 |
Loans, percentage of portfolio | 34.40% | 30.80% |
Loans, percentage of change in loans | 35.80% |  |
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) | $ 30,958,000 | $ 29,826,000 |
Loans, percentage of portfolio | 2.00% | 2.40% |
Loans, percentage of change in loans | 3.80% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 306,539,000 | $ 291,758,000 |
Loans, percentage of portfolio | 20.20% | 23.40% |
Loans, percentage of change in loans | 5.10% |  |
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) | $ 505,715,000 | $ 410,977,000 |
Loans, percentage of portfolio | 33.30% | 33.00% |
Loans, percentage of change in loans | 23.10% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Retail Portfolio Segment [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 36,762,000 | $ 36,058,000 |
Loans, percentage of portfolio | 2.40% | 2.90% |
Loans, percentage of change in loans | 2.00% |  |
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) | $ 36,762,000 | $ 36,058,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 475,300,000 | $ 562,114,000 |
Loans, percentage of portfolio | 68.10% | 66.60% |
Loans, percentage of change in loans | (15.40%) |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 120,772,000 | $ 166,037,000 |
Loans, percentage of portfolio | 17.30% | 19.70% |
Loans, percentage of change in loans | (27.30%) |  |
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) | $ 16,776,000 | $ 22,148,000 |
Loans, percentage of portfolio | 2.40% | 2.60% |
Loans, percentage of change in loans | (24.30%) |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 120,477,000 | $ 138,630,000 |
Loans, percentage of portfolio | 17.30% | 16.40% |
Loans, percentage of change in loans | (13.10%) |  |
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) | $ 130,512,000 | $ 148,597,000 |
Loans, percentage of portfolio | 18.70% | 17.60% |
Loans, percentage of change in loans | (12.20%) |  |
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) | $ 86,763,000 | $ 86,702,000 |
Loans, percentage of portfolio | 12.40% | 10.30% |
Loans, percentage of change in loans | 0.10% |  |
Retail Portfolio Segment [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 339,768,000 | $ 373,974,000 |
Loans, percentage of portfolio | 15.30% | 17.90% |
Loans, percentage of change in loans | (9.10%) |  |
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 146,765,000 | $ 159,278,000 |
Loans, percentage of portfolio | 6.60% | 7.60% |
Loans, percentage of change in loans | (7.90%) |  |
Retail Portfolio Segment [Member] | 1-4 Family Mortgages [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 193,003,000 | $ 214,696,000 |
Loans, percentage of portfolio | 8.70% | 10.30% |
Loans, percentage of change in loans | (10.10%) |  |
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 117,390,000 | $ 92,927,000 | $ 82,911,000
Loans, percentage of portfolio | 7.70% | 7.50% |
Loans, percentage of change in loans | 26.30% |  |
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 65,671,000 | $ 50,059,000 |
Loans, percentage of portfolio | 4.30% | 4.00% |
Loans, percentage of change in loans | 31.20% |  |
Retail Portfolio Segment [Member] | Originated Loan [Member] | 1-4 Family Mortgages [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 51,719,000 | $ 42,868,000 |
Loans, percentage of portfolio | 3.40% | 3.50% |
Loans, percentage of change in loans | 20.60% |  |
Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 222,378,000 | $ 281,047,000 |
Loans, percentage of portfolio | 31.90% | 33.40% |
Loans, percentage of change in loans | (20.90%) |  |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 81,094,000 | $ 109,219,000 |
Loans, percentage of portfolio | 11.60% | 13.00% |
Loans, percentage of change in loans | (25.80%) |  |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | 1-4 Family Mortgages [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Loans (in Dollars) | $ 141,284,000 | $ 171,828,000 |
Loans, percentage of portfolio | 20.30% | 20.40% |
Loans, percentage of change in loans | (17.80%) |  |

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