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Note 4 - Loans and Allowance for Loan Losses (Details) - Loans by Credit Quality Indicators - USD ($) | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
--- | --- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | $ 2,277,727,000 | $ 2,089,277,000 |
Originated Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 1,616,587,000 | 1,246,116,000 | $ 1,053,243,000
Acquired Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 661,140,000 | 843,161,000 |
Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 1,946,696,000 | 1,715,303,000 |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 696,303,000 | 550,607,000 |
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 45,120,000 | 51,974,000 |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 445,919,000 | 430,388,000 |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 644,351,000 | 559,574,000 |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 115,003,000 | 122,760,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 1,493,516,000 | 1,153,189,000 | $ 986,696,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 577,872,000 | 384,570,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 417,120,000 | 266,631,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 160,454,000 | 109,639,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 298,000 | 8,300,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 30,138,000 | 29,826,000 |
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 | 18,118,000 | 11,242,000 |
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 | 10,365,000 | 16,375,000 |
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 | 1,655,000 | 2,209,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 330,798,000 | 291,758,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 230,629,000 | 190,656,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 98,332,000 | 83,123,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 1,837,000 | 17,979,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 520,754,000 | 410,977,000 |
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 | 400,350,000 | 285,035,000 |
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 | 120,404,000 | 113,982,000 |
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 | 0 | 11,960,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 33,954,000 | 36,058,000 |
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 | 19,121,000 | 12,394,000 |
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 | 13,806,000 | 22,282,000 |
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 | 1,027,000 | 1,382,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 453,180,000 | 562,114,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 118,431,000 | 166,037,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 67,978,000 | 72,411,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 47,589,000 | 90,320,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 2,864,000 | 3,306,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 14,982,000 | 22,148,000 |
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 | 3,095,000 | 5,875,000 |
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 | 11,364,000 | 14,472,000 |
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 | 523,000 | 1,801,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 115,121,000 | 138,630,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] | Grade 1 - 4 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 45,807,000 | 39,496,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] | Grade 5 - 7 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 63,563,000 | 92,212,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] | Grade 8 - 9 [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 5,751,000 | 6,922,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 123,597,000 | 148,597,000 |
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 | 71,197,000 | 65,886,000 |
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 | 50,066,000 | 78,103,000 |
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 | 2,334,000 | 4,608,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 81,049,000 | 86,702,000 |
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 | 44,763,000 | 35,858,000 |
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 | 35,288,000 | 49,781,000 |
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 | $ 998,000 | $ 1,063,000 |

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