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Note 4 - Loans and Allowance for Loan Losses (Details) - Loans by Credit Quality Indicators - USD ($) | Jun. 30, 2015 | Dec. 31, 2014 | Jun. 30, 2014
--- | --- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | $ 2,171,832,000 | $ 2,089,277,000 |
Originated Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 1,429,623,000 | 1,246,116,000 | $ 1,145,097,000
Acquired Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 742,209,000 | 843,161,000 |
Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 1,820,431,000 | 1,715,303,000 |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 622,073,000 | 550,607,000 |
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 47,622,000 | 51,974,000 |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 422,354,000 | 430,388,000 |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 603,724,000 | 559,574,000 |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 124,658,000 | 122,760,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 1,322,388,000 | 1,153,189,000 | $ 1,076,609,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 487,440,000 | 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 | 348,542,000 | 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 | 136,948,000 | 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 | 1,950,000 | 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 | 28,853,000 | 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 | 15,243,000 | 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 | 11,426,000 | 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 | 2,184,000 | 2,209,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 297,694,000 | 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 | 211,066,000 | 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 | 83,907,000 | 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 | 2,721,000 | 17,979,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 469,433,000 | 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 | 342,030,000 | 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 | 121,726,000 | 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 | 5,677,000 | 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 | 38,968,000 | 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 | 16,044,000 | 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 | 21,619,000 | 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 | 1,305,000 | 1,382,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 498,043,000 | 562,114,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 134,633,000 | 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 | 59,441,000 | 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 | 71,999,000 | 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 | 3,193,000 | 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 | 18,769,000 | 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 | 5,382,000 | 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 | 12,177,000 | 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 | 1,210,000 | 1,801,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 124,660,000 | 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 | 44,922,000 | 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 | 73,383,000 | 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 | 6,355,000 | 6,922,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 134,291,000 | 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 | 67,258,000 | 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 | 63,716,000 | 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 | 3,317,000 | 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 | 85,690,000 | 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 | 41,488,000 | 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 | 40,329,000 | 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 | $ 3,873,000 | $ 1,063,000 |

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