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Note 3 - Loans and Allowance for Loan Losses (Details) - Loans by Credit Quality Indicators - USD ($) | Mar. 31, 2016 | Dec. 31, 2015 | Mar. 31, 2015
--- | --- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | $ 2,295,668,000 | $ 2,277,727,000 |
Originated Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 1,687,476,000 | 1,616,587,000 | $ 1,328,713,000
Acquired Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 608,192,000 | 661,140,000 |
Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 1,974,450,000 | 1,946,696,000 |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 714,612,000 | 696,303,000 |
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 39,630,000 | 45,120,000 |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 441,662,000 | 445,919,000 |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 666,013,000 | 644,351,000 |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 112,533,000 | 115,003,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 1,562,777,000 | 1,493,516,000 | $ 1,230,841,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 613,570,000 | 577,872,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 417,049,000 | 417,120,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 196,431,000 | 160,454,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 90,000 | 298,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 28,451,000 | 30,138,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 16,694,000 | 18,118,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 11,617,000 | 10,365,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 140,000 | 1,655,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 334,948,000 | 330,798,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 231,625,000 | 230,629,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 101,552,000 | 98,332,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 1,771,000 | 1,837,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 549,226,000 | 520,754,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 434,645,000 | 400,350,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 114,581,000 | 120,404,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 0 | 0 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 36,582,000 | 33,954,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 19,947,000 | 19,121,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 15,629,000 | 13,806,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 1,006,000 | 1,027,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 411,673,000 | 453,180,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 101,042,000 | 118,431,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 51,717,000 | 67,978,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 46,749,000 | 47,589,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 2,576,000 | 2,864,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 11,179,000 | 14,982,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 2,892,000 | 3,095,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 7,811,000 | 11,364,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 476,000 | 523,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 106,714,000 | 115,121,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 43,806,000 | 45,807,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 58,971,000 | 63,563,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 3,937,000 | 5,751,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 116,787,000 | 123,597,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 66,096,000 | 71,197,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 48,792,000 | 50,066,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 1,899,000 | 2,334,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 75,951,000 | 81,049,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 42,159,000 | 44,763,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | 33,071,000 | 35,288,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans, credit exposure | $ 721,000 | $ 998,000 |

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