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Note 3 - Loans and Allowance for Loan Losses (Details) - Components of Loan Portfolio - USD ($) | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2016 | Dec. 31, 2015 | Mar. 31, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 2,295,668,000 | $ 2,277,727,000 |
Percent of portfolio | 100.00% | 100.00% |
Period increase (decrease) | 0.80% |  |
Originated Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 1,687,476,000 | $ 1,616,587,000 | $ 1,328,713,000
Percent of portfolio | 100.00% | 100.00% |
Period increase (decrease) | 4.40% |  |
Acquired Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 608,192,000 | $ 661,140,000 |
Percent of portfolio | 100.00% | 100.00% |
Period increase (decrease) | (8.00%) |  |
Commercial Portfolio Segment [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 1,974,450,000 | $ 1,946,696,000 |
Percent of portfolio | 86.00% | 85.50% |
Period increase (decrease) | 1.40% |  |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 714,612,000 | $ 696,303,000 |
Percent of portfolio | 31.10% | 30.60% |
Period increase (decrease) | 2.60% |  |
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 39,630,000 | $ 45,120,000 |
Percent of portfolio | 1.70% | 2.00% |
Period increase (decrease) | (12.20%) |  |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 441,662,000 | $ 445,919,000 |
Percent of portfolio | 19.30% | 19.60% |
Period increase (decrease) | (1.00%) |  |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 666,013,000 | $ 644,351,000 |
Percent of portfolio | 29.00% | 28.30% |
Period increase (decrease) | 3.40% |  |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 112,533,000 | $ 115,003,000 |
Percent of portfolio | 4.90% | 5.00% |
Period increase (decrease) | (2.10%) |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 1,562,777,000 | $ 1,493,516,000 | 1,230,841,000
Percent of portfolio | 92.60% | 92.40% |
Period increase (decrease) | 4.60% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 613,570,000 | $ 577,872,000 |
Percent of portfolio | 36.40% | 35.70% |
Period increase (decrease) | 6.20% |  |
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] |  |  |
Balance of loans outstanding (in Dollars) | $ 28,451,000 | $ 30,138,000 |
Percent of portfolio | 1.70% | 1.90% |
Period increase (decrease) | (5.60%) |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 334,948,000 | $ 330,798,000 |
Percent of portfolio | 19.80% | 20.50% |
Period increase (decrease) | 1.30% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 549,226,000 | $ 520,754,000 |
Percent of portfolio | 32.50% | 32.20% |
Period increase (decrease) | 5.50% |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 36,582,000 | $ 33,954,000 |
Percent of portfolio | 2.20% | 2.10% |
Period increase (decrease) | 7.70% |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 411,673,000 | $ 453,180,000 |
Percent of portfolio | 67.70% | 68.60% |
Period increase (decrease) | (9.20%) |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 101,042,000 | $ 118,431,000 |
Percent of portfolio | 16.60% | 17.90% |
Period increase (decrease) | (14.70%) |  |
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] |  |  |
Balance of loans outstanding (in Dollars) | $ 11,179,000 | $ 14,982,000 |
Percent of portfolio | 1.90% | 2.30% |
Period increase (decrease) | (25.40%) |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 106,714,000 | $ 115,121,000 |
Percent of portfolio | 17.50% | 17.40% |
Period increase (decrease) | (7.30%) |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 116,787,000 | $ 123,597,000 |
Percent of portfolio | 19.20% | 18.70% |
Period increase (decrease) | (5.50%) |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 75,951,000 | $ 81,049,000 |
Percent of portfolio | 12.50% | 12.30% |
Period increase (decrease) | (6.30%) |  |
Retail Portfolio Segment [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 321,218,000 | $ 331,031,000 |
Percent of portfolio | 14.00% | 14.50% |
Period increase (decrease) | (3.00%) |  |
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 135,683,000 | $ 140,646,000 |
Percent of portfolio | 5.90% | 6.20% |
Period increase (decrease) | (3.50%) |  |
Retail Portfolio Segment [Member] | 1-4 Family Mortgages [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 185,535,000 | $ 190,385,000 |
Percent of portfolio | 8.10% | 8.30% |
Period increase (decrease) | (2.50%) |  |
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 124,699,000 | $ 123,071,000 | $ 97,872,000
Percent of portfolio | 7.40% | 7.60% |
Period increase (decrease) | 1.30% |  |
Retail Portfolio Segment [Member] | Originated Loan [Member] | Home Equity and Other [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 68,342,000 | $ 67,816,000 |
Percent of portfolio | 4.10% | 4.20% |
Period increase (decrease) | 0.80% |  |
Retail Portfolio Segment [Member] | Originated Loan [Member] | 1-4 Family Mortgages [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 56,357,000 | $ 55,255,000 |
Percent of portfolio | 3.30% | 3.40% |
Period increase (decrease) | 2.00% |  |
Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 196,519,000 | $ 207,960,000 |
Percent of portfolio | 32.30% | 31.40% |
Period increase (decrease) | (5.50%) |  |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | Home Equity and Other [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 67,341,000 | $ 72,830,000 |
Percent of portfolio | 11.10% | 11.00% |
Period increase (decrease) | (7.50%) |  |
Retail Portfolio Segment [Member] | Acquired Loan [Member] | 1-4 Family Mortgages [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 129,178,000 | $ 135,130,000 |
Percent of portfolio | 21.20% | 20.40% |
Period increase (decrease) | (4.40%) |  |

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