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Note 4 - Loans and Allowance for Loan Losses (Details) - Impaired Loans (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 9 Months Ended |
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Sep. 30, 2014 | Sep. 30, 2013 | Sep. 30, 2014 | Sep. 30, 2013 | Dec. 31, 2013
Commercial: |  |  |  |  |
Impaired loans with no related allowance recorded, unpaid contractual principal balance | $ 23,678,000 |  | $ 23,678,000 |  | $ 6,689,000
Impaired loans with no related allowance recorded, recorded principal balance | 21,048,000 |  | 21,048,000 |  | 3,500,000
Impaired loans with no related allowance recorded, average recorded principal balance | 11,800,000 | 9,199,000 | 7,838,000 | 10,270,000 |
Commercial: |  |  |  |  |
Impaired loans with an allowance recorded, unpaid contractual principal balance | 31,627,000 |  | 31,627,000 |  | 34,367,000
Impaired loans with an allowance recorded, recorded principal balance | 31,168,000 |  | 31,168,000 |  | 33,368,000
Impaired loans, related allowance | 11,364,000 |  | 11,364,000 |  | 12,386,000
Impaired loans with an allowance recorded, average recorded principal balance | 29,611,000 | 42,777,000 | 30,432,000 | 42,963,000 |
Total impaired loans: |  |  |  |  |
Impaired loans, unpaid contractual principal balance | 55,305,000 |  | 55,305,000 |  | 41,056,000
Impaired loans, recorded principal balance | 52,216,000 |  | 52,216,000 |  | 36,868,000
Impaired loans, related allowance | 11,364,000 |  | 11,364,000 |  | 12,386,000
Impaired loans, average recorded principal balance | 41,411,000 | 51,976,000 | 38,270,000 | 53,233,000 |
Commercial and Industrial [Member] |  |  |  |  |
Commercial: |  |  |  |  |
Impaired loans with no related allowance recorded, unpaid contractual principal balance | 1,250,000 |  | 1,250,000 |  | 2,229,000
Impaired loans with no related allowance recorded, recorded principal balance | 1,250,000 |  | 1,250,000 |  | 511,000
Impaired loans with no related allowance recorded, average recorded principal balance | 691,000 | 1,170,000 | 525,000 | 1,378,000 |
Commercial: |  |  |  |  |
Impaired loans with an allowance recorded, unpaid contractual principal balance | 5,404,000 |  | 5,404,000 |  | 1,517,000
Impaired loans with an allowance recorded, recorded principal balance | 5,363,000 |  | 5,363,000 |  | 1,440,000
Impaired loans, related allowance | 2,251,000 |  | 2,251,000 |  | 792,000
Impaired loans with an allowance recorded, average recorded principal balance | 3,087,000 | 1,764,000 | 2,142,000 | 1,990,000 |
Total impaired loans: |  |  |  |  |
Impaired loans, related allowance | 2,251,000 |  | 2,251,000 |  | 792,000
Commercial Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |  |  |
Commercial: |  |  |  |  |
Impaired loans with no related allowance recorded, unpaid contractual principal balance | 545,000 |  | 545,000 |  | 475,000
Impaired loans with no related allowance recorded, recorded principal balance | 222,000 |  | 222,000 |  | 362,000
Impaired loans with no related allowance recorded, average recorded principal balance | 111,000 | 907,000 | 232,000 | 1,148,000 |
Commercial: |  |  |  |  |
Impaired loans with an allowance recorded, unpaid contractual principal balance | 2,798,000 |  | 2,798,000 |  | 4,436,000
Impaired loans with an allowance recorded, recorded principal balance | 2,798,000 |  | 2,798,000 |  | 4,139,000
Impaired loans, related allowance | 318,000 |  | 318,000 |  | 844,000
Impaired loans with an allowance recorded, average recorded principal balance | 3,049,000 | 4,466,000 | 3,536,000 | 3,158,000 |
Total impaired loans: |  |  |  |  |
Impaired loans, related allowance | 318,000 |  | 318,000 |  | 844,000
Commercial Real Estate Owner Occupied Loan [Member] |  |  |  |  |
Commercial: |  |  |  |  |
Impaired loans with no related allowance recorded, unpaid contractual principal balance | 19,499,000 |  | 19,499,000 |  | 1,270,000
Impaired loans with no related allowance recorded, recorded principal balance | 17,815,000 |  | 17,815,000 |  | 785,000
Impaired loans with no related allowance recorded, average recorded principal balance | 9,227,000 | 865,000 | 4,981,000 | 1,159,000 |
Commercial: |  |  |  |  |
Impaired loans with an allowance recorded, unpaid contractual principal balance | 2,218,000 |  | 2,218,000 |  | 1,513,000
Impaired loans with an allowance recorded, recorded principal balance | 2,016,000 |  | 2,016,000 |  | 1,513,000
Impaired loans, related allowance | 628,000 |  | 628,000 |  | 528,000
Impaired loans with an allowance recorded, average recorded principal balance | 2,238,000 | 2,330,000 | 1,869,000 | 2,810,000 |
Total impaired loans: |  |  |  |  |
Impaired loans, related allowance | 628,000 |  | 628,000 |  | 528,000
Commercial Real Estate Non Owner Occupied Loan [Member] |  |  |  |  |
Commercial: |  |  |  |  |
Impaired loans with no related allowance recorded, unpaid contractual principal balance | 575,000 |  | 575,000 |  | 895,000
Impaired loans with no related allowance recorded, recorded principal balance | 575,000 |  | 575,000 |  | 733,000
Impaired loans with no related allowance recorded, average recorded principal balance | 576,000 | 4,651,000 | 911,000 | 4,878,000 |
Commercial: |  |  |  |  |
Impaired loans with an allowance recorded, unpaid contractual principal balance | 17,023,000 |  | 17,023,000 |  | 21,088,000
Impaired loans with an allowance recorded, recorded principal balance | 17,023,000 |  | 17,023,000 |  | 21,072,000
Impaired loans, related allowance | 6,489,000 |  | 6,489,000 |  | 7,969,000
Impaired loans with an allowance recorded, average recorded principal balance | 17,377,000 | 28,789,000 | 18,819,000 | 30,216,000 |
Total impaired loans: |  |  |  |  |
Impaired loans, related allowance | 6,489,000 |  | 6,489,000 |  | 7,969,000
Commercial Real Estate Multi Family and Residential Rental Loan [Member] |  |  |  |  |
Commercial: |  |  |  |  |
Impaired loans with no related allowance recorded, unpaid contractual principal balance | 0 |  | 0 |  | 41,000
Impaired loans with no related allowance recorded, recorded principal balance | 0 |  | 0 |  | 1,000
Impaired loans with no related allowance recorded, average recorded principal balance | 0 | 425,000 | 0 | 487,000 |
Commercial: |  |  |  |  |
Impaired loans with an allowance recorded, unpaid contractual principal balance | 1,861,000 |  | 1,861,000 |  | 3,219,000
Impaired loans with an allowance recorded, recorded principal balance | 1,808,000 |  | 1,808,000 |  | 2,684,000
Impaired loans, related allowance | 799,000 |  | 799,000 |  | 1,127,000
Impaired loans with an allowance recorded, average recorded principal balance | 1,679,000 | 2,639,000 | 1,783,000 | 2,973,000 |
Total impaired loans: |  |  |  |  |
Impaired loans, related allowance | 799,000 |  | 799,000 |  | 1,127,000
Commercial Portfolio Segment [Member] |  |  |  |  |
Commercial: |  |  |  |  |
Impaired loans with no related allowance recorded, unpaid contractual principal balance | 21,869,000 |  | 21,869,000 |  | 4,910,000
Impaired loans with no related allowance recorded, recorded principal balance | 19,862,000 |  | 19,862,000 |  | 2,392,000
Impaired loans with no related allowance recorded, average recorded principal balance | 10,605,000 | 8,018,000 | 6,649,000 | 9,050,000 |
Commercial: |  |  |  |  |
Impaired loans with an allowance recorded, unpaid contractual principal balance | 29,304,000 |  | 29,304,000 |  | 31,773,000
Impaired loans with an allowance recorded, recorded principal balance | 29,008,000 |  | 29,008,000 |  | 30,848,000
Impaired loans, related allowance | 10,485,000 |  | 10,485,000 |  | 11,260,000
Impaired loans with an allowance recorded, average recorded principal balance | 27,430,000 | 39,988,000 | 28,149,000 | 41,147,000 |
Total impaired loans: |  |  |  |  |
Impaired loans, unpaid contractual principal balance | 51,173,000 |  | 51,173,000 |  | 36,683,000
Impaired loans, recorded principal balance | 48,870,000 |  | 48,870,000 |  | 33,240,000
Impaired loans, related allowance | 10,485,000 |  | 10,485,000 |  | 11,260,000
Impaired loans, average recorded principal balance | 38,035,000 | 48,006,000 | 34,798,000 | 50,197,000 |
Retail Home Equity and Other [Member] |  |  |  |  |
Commercial: |  |  |  |  |
Impaired loans with no related allowance recorded, unpaid contractual principal balance | 707,000 |  | 707,000 |  | 507,000
Impaired loans with no related allowance recorded, recorded principal balance | 639,000 |  | 639,000 |  | 461,000
Impaired loans with no related allowance recorded, average recorded principal balance | 642,000 | 466,000 | 598,000 | 474,000 |
Commercial: |  |  |  |  |
Impaired loans with an allowance recorded, unpaid contractual principal balance | 117,000 |  | 117,000 |  | 320,000
Impaired loans with an allowance recorded, recorded principal balance | 87,000 |  | 87,000 |  | 289,000
Impaired loans, related allowance | 87,000 |  | 87,000 |  | 96,000
Impaired loans with an allowance recorded, average recorded principal balance | 88,000 | 309,000 | 139,000 | 339,000 |
Total impaired loans: |  |  |  |  |
Impaired loans, related allowance | 87,000 |  | 87,000 |  | 96,000
Retail 1-4 Family Mortgages [Member] |  |  |  |  |
Commercial: |  |  |  |  |
Impaired loans with no related allowance recorded, unpaid contractual principal balance | 1,102,000 |  | 1,102,000 |  | 1,272,000
Impaired loans with no related allowance recorded, recorded principal balance | 547,000 |  | 547,000 |  | 647,000
Impaired loans with no related allowance recorded, average recorded principal balance | 553,000 | 715,000 | 591,000 | 746,000 |
Commercial: |  |  |  |  |
Impaired loans with an allowance recorded, unpaid contractual principal balance | 2,206,000 |  | 2,206,000 |  | 2,274,000
Impaired loans with an allowance recorded, recorded principal balance | 2,073,000 |  | 2,073,000 |  | 2,231,000
Impaired loans, related allowance | 792,000 |  | 792,000 |  | 1,030,000
Impaired loans with an allowance recorded, average recorded principal balance | 2,093,000 | 2,480,000 | 2,144,000 | 1,477,000 |
Total impaired loans: |  |  |  |  |
Impaired loans, related allowance | 792,000 |  | 792,000 |  | 1,030,000
Retail Loan [Member] |  |  |  |  |
Commercial: |  |  |  |  |
Impaired loans with no related allowance recorded, unpaid contractual principal balance | 1,809,000 |  | 1,809,000 |  | 1,779,000
Impaired loans with no related allowance recorded, recorded principal balance | 1,186,000 |  | 1,186,000 |  | 1,108,000
Impaired loans with no related allowance recorded, average recorded principal balance | 1,195,000 | 1,181,000 | 1,189,000 | 1,220,000 |
Commercial: |  |  |  |  |
Impaired loans with an allowance recorded, unpaid contractual principal balance | 2,323,000 |  | 2,323,000 |  | 2,594,000
Impaired loans with an allowance recorded, recorded principal balance | 2,160,000 |  | 2,160,000 |  | 2,520,000
Impaired loans, related allowance | 879,000 |  | 879,000 |  | 1,126,000
Impaired loans with an allowance recorded, average recorded principal balance | 2,181,000 | 2,789,000 | 2,283,000 | 1,816,000 |
Total impaired loans: |  |  |  |  |
Impaired loans, unpaid contractual principal balance | 4,132,000 |  | 4,132,000 |  | 4,373,000
Impaired loans, recorded principal balance | 3,346,000 |  | 3,346,000 |  | 3,628,000
Impaired loans, related allowance | 879,000 |  | 879,000 |  | 1,126,000
Impaired loans, average recorded principal balance | $ 3,376,000 | $ 3,970,000 | $ 3,472,000 | $ 3,036,000 |

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