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Note 4 - Loans and Allowance for Loan Losses - Components of Loan Portfolio (Details) - USD ($) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Loans | $ 2,856,667,000 | $ 2,753,085,000 |
Percent of portfolio | 100.00% | 100.00% |
Period increase (decrease) | 3.80% |  |
Commercial Portfolio Segment [Member] |  |  |
Loans | $ 2,441,544,000 | $ 2,360,106,000 |
Percent of portfolio | 85.50% | 85.70% |
Period increase (decrease) | 3.50% |  |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Loans | $ 846,551,000 | $ 822,723,000 |
Percent of portfolio | 29.60% | 29.90% |
Period increase (decrease) | 2.90% |  |
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Loans | $ 56,119,000 | $ 44,885,000 |
Percent of portfolio | 2.00% | 1.60% |
Period increase (decrease) | 25.00% |  |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Loans | $ 579,003,000 | $ 548,619,000 |
Percent of portfolio | 20.30% | 19.90% |
Period increase (decrease) | 5.50% |  |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Loans | $ 835,346,000 | $ 816,282,000 |
Percent of portfolio | 29.20% | 29.70% |
Period increase (decrease) | 2.30% |  |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Loans | $ 124,525,000 | $ 127,597,000 |
Percent of portfolio | 4.40% | 4.60% |
Period increase (decrease) | (2.40%) |  |
Retail Portfolio Segment [Member] |  |  |
Loans | $ 415,123,000 | $ 392,979,000 |
Percent of portfolio | 14.50% | 14.30% |
Period increase (decrease) | 5.60% |  |
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Loans | $ 75,374,000 | $ 85,439,000 |
Percent of portfolio | 2.60% | 3.10% |
Period increase (decrease) | (11.80%) |  |
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Loans | $ 339,749,000 | $ 307,540,000 |
Percent of portfolio | 11.90% | 11.20% |
Period increase (decrease) | 10.50% |  |
Originated Loan [Member] |  |  |
Loans | $ 2,614,725,000 | $ 2,452,446,000 | $ 2,169,957,000
Percent of portfolio | 100.00% | 100.00% |
Period increase (decrease) | 6.60% |  |
Originated Loan [Member] | Commercial Portfolio Segment [Member] |  |  |
Loans | $ 2,271,417,000 | $ 2,151,998,000 | 1,934,228,000
Percent of portfolio | 86.90% | 87.70% |
Period increase (decrease) | 5.50% |  |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Loans | $ 799,421,000 | $ 768,698,000 |
Percent of portfolio | 30.60% | 31.30% |
Period increase (decrease) | 4.00% |  |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Loans | $ 52,097,000 | $ 39,950,000 |
Percent of portfolio | 2.00% | 1.60% |
Period increase (decrease) | 30.40% |  |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Loans | $ 542,561,000 | $ 500,188,000 |
Percent of portfolio | 20.80% | 20.40% |
Period increase (decrease) | 8.50% |  |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Loans | $ 776,994,000 | $ 745,127,000 |
Percent of portfolio | 29.70% | 30.40% |
Period increase (decrease) | 4.30% |  |
Originated Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Loans | $ 100,344,000 | $ 98,035,000 |
Percent of portfolio | 3.80% | 4.00% |
Period increase (decrease) | 2.40% |  |
Originated Loan [Member] | Retail Portfolio Segment [Member] |  |  |
Loans | $ 343,308,000 | $ 300,448,000 | $ 235,729,000
Percent of portfolio | 13.10% | 12.30% |
Period increase (decrease) | 14.30% |  |
Originated Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Loans | $ 61,060,000 | $ 65,023,000 |
Percent of portfolio | 2.30% | 2.70% |
Period increase (decrease) | (6.10%) |  |
Originated Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Loans | $ 282,248,000 | $ 235,425,000 |
Percent of portfolio | 10.80% | 9.60% |
Period increase (decrease) | 19.90% |  |
Acquired Loan [Member] |  |  |
Loans | $ 241,942,000 | $ 300,639,000 |
Percent of portfolio | 100.00% | 100.00% |
Period increase (decrease) | (19.50%) |  |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] |  |  |
Loans | $ 170,127,000 | $ 208,108,000 |
Percent of portfolio | 70.30% | 69.20% |
Period increase (decrease) | (18.30%) |  |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Loans | $ 47,130,000 | $ 54,025,000 |
Percent of portfolio | 19.40% | 18.00% |
Period increase (decrease) | (12.80%) |  |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Loans | $ 4,022,000 | $ 4,935,000 |
Percent of portfolio | 1.70% | 1.60% |
Period increase (decrease) | (18.50%) |  |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Loans | $ 36,442,000 | $ 48,431,000 |
Percent of portfolio | 15.10% | 16.10% |
Period increase (decrease) | (24.80%) |  |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Loans | $ 58,352,000 | $ 71,155,000 |
Percent of portfolio | 24.10% | 23.70% |
Period increase (decrease) | (18.00%) |  |
Acquired Loan [Member] | Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Loans | $ 24,181,000 | $ 29,562,000 |
Percent of portfolio | 10.00% | 9.80% |
Period increase (decrease) | (18.20%) |  |
Acquired Loan [Member] | Retail Portfolio Segment [Member] |  |  |
Loans | $ 71,815,000 | $ 92,531,000 |
Percent of portfolio | 29.70% | 30.80% |
Period increase (decrease) | (22.40%) |  |
Acquired Loan [Member] | Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |  |
Loans | $ 14,314,000 | $ 20,416,000 |
Percent of portfolio | 5.90% | 6.80% |
Period increase (decrease) | (29.90%) |  |
Acquired Loan [Member] | Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |  |
Loans | $ 57,501,000 | $ 72,115,000 |
Percent of portfolio | 23.80% | 24.00% |
Period increase (decrease) | (20.30%) |  |

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