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Note 4 - Loans and Allowance for Loan Losses - Components of Loan Portfolio (Details) - USD ($) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Loans | $ 2,378,620,000 | $ 2,277,727,000 |
Percent of portfolio | 100.00% | 100.00% |
Period increase (decrease) | 4.40% |  |
Commercial Portfolio Segment [Member] |  |  |
Loans | $ 2,065,347,000 | $ 1,946,696,000 |
Percent of portfolio | 86.80% | 85.50% |
Period increase (decrease) | 6.10% |  |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Loans | $ 713,903,000 | $ 696,303,000 |
Percent of portfolio | 30.00% | 30.60% |
Period increase (decrease) | 2.50% |  |
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Loans | $ 34,828,000 | $ 45,120,000 |
Percent of portfolio | 1.50% | 2.00% |
Period increase (decrease) | (22.80%) |  |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Loans | $ 450,464,000 | $ 445,919,000 |
Percent of portfolio | 18.90% | 19.60% |
Period increase (decrease) | 1.00% |  |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Loans | $ 748,269,000 | $ 644,351,000 |
Percent of portfolio | 31.50% | 28.30% |
Period increase (decrease) | 16.10% |  |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |  |
Loans | $ 117,883,000 | $ 115,003,000 |
Percent of portfolio | 4.90% | 5.00% |
Period increase (decrease) | 2.50% |  |
Retail Portfolio Segment [Member] |  |  |
Loans | $ 313,273,000 | $ 331,031,000 |
Percent of portfolio | 13.20% | 14.50% |
Period increase (decrease) | (5.40%) |  |
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Loans | $ 118,047,000 | $ 140,646,000 |
Percent of portfolio | 5.00% | 6.20% |
Period increase (decrease) | (16.10%) |  |
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Loans | $ 195,226,000 | $ 190,385,000 |
Percent of portfolio | 8.20% | 8.30% |
Period increase (decrease) | 2.50% |  |
Originated Loan [Member] |  |  |
Loans | $ 1,884,548,000 | $ 1,616,587,000 | $ 1,246,116,000
Percent of portfolio | 100.00% | 100.00% |
Period increase (decrease) | 16.60% |  |
Originated Loan [Member] | Commercial Portfolio Segment [Member] |  |  |
Loans | $ 1,728,898,000 | $ 1,493,516,000 | 1,153,189,000
Percent of portfolio | 91.70% | 92.40% |
Period increase (decrease) | 15.80% |  |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Loans | $ 636,771,000 | $ 577,872,000 |
Percent of portfolio | 33.80% | 35.70% |
Period increase (decrease) | 10.20% |  |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Loans | $ 26,519,000 | $ 30,138,000 |
Percent of portfolio | 1.40% | 1.90% |
Period increase (decrease) | (12.00%) |  |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Loans | $ 363,509,000 | $ 330,798,000 |
Percent of portfolio | 19.30% | 20.50% |
Period increase (decrease) | 9.90% |  |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Loans | $ 652,054,000 | $ 520,754,000 |
Percent of portfolio | 34.60% | 32.20% |
Period increase (decrease) | 25.20% |  |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |  |
Loans | $ 50,045,000 | $ 33,954,000 |
Percent of portfolio | 2.60% | 2.10% |
Period increase (decrease) | 47.40% |  |
Originated Loan [Member] | Retail Portfolio Segment [Member] |  |  |
Loans | $ 155,650,000 | $ 123,071,000 | $ 92,927,000
Percent of portfolio | 8.30% | 7.60% |
Period increase (decrease) | 26.50% |  |
Originated Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Loans | $ 69,831,000 | $ 67,816,000 |
Percent of portfolio | 3.70% | 4.20% |
Period increase (decrease) | 3.00% |  |
Originated Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Loans | $ 85,819,000 | $ 55,255,000 |
Percent of portfolio | 4.60% | 3.40% |
Period increase (decrease) | 55.30% |  |
Acquired Loan [Member] |  |  |
Loans | $ 494,072,000 | $ 661,140,000 |
Percent of portfolio | 100.00% | 100.00% |
Period increase (decrease) | (25.30%) |  |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] |  |  |
Loans | $ 336,449,000 | $ 453,180,000 |
Percent of portfolio | 68.10% | 68.60% |
Period increase (decrease) | (25.80%) |  |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Loans | $ 77,132,000 | $ 118,431,000 |
Percent of portfolio | 15.60% | 17.90% |
Period increase (decrease) | (34.90%) |  |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Loans | $ 8,309,000 | $ 14,982,000 |
Percent of portfolio | 1.70% | 2.30% |
Period increase (decrease) | (44.50%) |  |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Loans | $ 86,955,000 | $ 115,121,000 |
Percent of portfolio | 17.60% | 17.40% |
Period increase (decrease) | (24.50%) |  |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Loans | $ 96,215,000 | $ 123,597,000 |
Percent of portfolio | 19.50% | 18.70% |
Period increase (decrease) | (22.20%) |  |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residentia lRental Loan [Member] |  |  |
Loans | $ 67,838,000 | $ 81,049,000 |
Percent of portfolio | 13.70% | 12.30% |
Period increase (decrease) | (16.30%) |  |
Acquired Loan [Member] | Retail Portfolio Segment [Member] |  |  |
Loans | $ 157,623,000 | $ 207,960,000 |
Percent of portfolio | 31.90% | 31.40% |
Period increase (decrease) | (24.20%) |  |
Acquired Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Loans | $ 48,216,000 | $ 72,830,000 |
Percent of portfolio | 9.80% | 11.00% |
Period increase (decrease) | (33.80%) |  |
Acquired Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Loans | $ 109,407,000 | $ 135,130,000 |
Percent of portfolio | 22.10% | 20.40% |
Period increase (decrease) | (19.00%) |  |

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