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Note 4 - Loans and Allowance for Loan Losses (Details) - Components of Loan Portfolio - USD ($) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 2,277,727,000 | $ 2,089,277,000 |
Percent of portfolio | 100.00% | 100.00% |
Period increase (decrease) | 9.00% |  |
Originated Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 1,616,587,000 | $ 1,246,116,000 | $ 1,053,243,000
Percent of portfolio | 100.00% | 100.00% |
Period increase (decrease) | 29.70% |  |
Acquired Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 661,140,000 | $ 843,161,000 |
Percent of portfolio | 100.00% | 100.00% |
Period increase (decrease) | (21.60%) |  |
Commercial Portfolio Segment [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 1,946,696,000 | $ 1,715,303,000 |
Percent of portfolio | 85.50% | 82.10% |
Period increase (decrease) | 13.50% |  |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 696,303,000 | $ 550,607,000 |
Percent of portfolio | 30.60% | 26.40% |
Period increase (decrease) | 26.50% |  |
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) | $ 45,120,000 | $ 51,974,000 |
Percent of portfolio | 2.00% | 2.50% |
Period increase (decrease) | (13.20%) |  |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 445,919,000 | $ 430,388,000 |
Percent of portfolio | 19.60% | 20.50% |
Period increase (decrease) | 3.60% |  |
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) | $ 644,351,000 | $ 559,574,000 |
Percent of portfolio | 28.30% | 26.80% |
Period increase (decrease) | 15.20% |  |
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) | $ 115,003,000 | $ 122,760,000 |
Percent of portfolio | 5.00% | 5.90% |
Period increase (decrease) | (6.30%) |  |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 1,493,516,000 | $ 1,153,189,000 | 986,696,000
Percent of portfolio | 92.40% | 92.50% |
Period increase (decrease) | 29.50% |  |
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) | $ 577,872,000 | $ 384,570,000 |
Percent of portfolio | 35.70% | 30.80% |
Period increase (decrease) | 50.30% |  |
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) | $ 30,138,000 | $ 29,826,000 |
Percent of portfolio | 1.90% | 2.40% |
Period increase (decrease) | 1.00% |  |
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) | $ 330,798,000 | $ 291,758,000 |
Percent of portfolio | 20.50% | 23.40% |
Period increase (decrease) | 13.40% |  |
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) | $ 520,754,000 | $ 410,977,000 |
Percent of portfolio | 32.20% | 33.00% |
Period increase (decrease) | 26.70% |  |
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) | $ 33,954,000 | $ 36,058,000 |
Percent of portfolio | 2.10% | 2.90% |
Period increase (decrease) | (5.80%) |  |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 453,180,000 | $ 562,114,000 |
Percent of portfolio | 68.60% | 66.60% |
Period increase (decrease) | (19.40%) |  |
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) | $ 118,431,000 | $ 166,037,000 |
Percent of portfolio | 17.90% | 19.70% |
Period increase (decrease) | (28.70%) |  |
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) | $ 14,982,000 | $ 22,148,000 |
Percent of portfolio | 2.30% | 2.60% |
Period increase (decrease) | (32.40%) |  |
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) | $ 115,121,000 | $ 138,630,000 |
Percent of portfolio | 17.40% | 16.40% |
Period increase (decrease) | (17.00%) |  |
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) | $ 123,597,000 | $ 148,597,000 |
Percent of portfolio | 18.70% | 17.60% |
Period increase (decrease) | (16.80%) |  |
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) | $ 81,049,000 | $ 86,702,000 |
Percent of portfolio | 12.30% | 10.30% |
Period increase (decrease) | (6.50%) |  |
Retail Portfolio Segment [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 331,031,000 | $ 373,974,000 |
Percent of portfolio | 14.50% | 17.90% |
Period increase (decrease) | (11.50%) |  |
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 140,646,000 | $ 159,278,000 |
Percent of portfolio | 6.20% | 7.60% |
Period increase (decrease) | (11.70%) |  |
Retail Portfolio Segment [Member] | 1-4 Family Mortgages [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 190,385,000 | $ 214,696,000 |
Percent of portfolio | 8.30% | 10.30% |
Period increase (decrease) | (11.30%) |  |
Retail Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 123,071,000 | $ 92,927,000 | $ 66,547,000
Percent of portfolio | 7.60% | 7.50% |
Period increase (decrease) | 32.40% |  |
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) | $ 67,816,000 | $ 50,059,000 |
Percent of portfolio | 4.20% | 4.00% |
Period increase (decrease) | 35.50% |  |
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) | $ 55,255,000 | $ 42,868,000 |
Percent of portfolio | 3.40% | 3.50% |
Period increase (decrease) | 28.90% |  |
Retail Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Balance of loans outstanding (in Dollars) | $ 207,960,000 | $ 281,047,000 |
Percent of portfolio | 31.40% | 33.40% |
Period increase (decrease) | (26.00%) |  |
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) | $ 72,830,000 | $ 109,219,000 |
Percent of portfolio | 11.00% | 13.00% |
Period increase (decrease) | (33.30%) |  |
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) | $ 135,130,000 | $ 171,828,000 |
Percent of portfolio | 20.40% | 20.40% |
Period increase (decrease) | (21.40%) |  |

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