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Note 3 - Loans and Allowance for Loan Losses (Details) - Loans by Credit Quality Indicators - USD ($) | Sep. 30, 2015 | Dec. 31, 2014 | Sep. 30, 2014
--- | --- | --- | ---
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | $ 2,217,388,000 | $ 2,089,277,000 |
Originated Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 1,519,710,000 | 1,246,116,000 | $ 1,186,713,000
Acquired Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 697,678,000 | 843,161,000 |
Commercial Portfolio Segment [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 1,877,620,000 | 1,715,303,000 |
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 643,118,000 | 550,607,000 |
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 47,734,000 | 51,974,000 |
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 427,016,000 | 430,388,000 |
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 636,227,000 | 559,574,000 |
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 123,525,000 | 122,760,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 1,402,320,000 | 1,153,189,000 | $ 1,103,802,000
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 522,346,000 | 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 | 363,211,000 | 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 | 158,699,000 | 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 | 436,000 | 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 | 30,958,000 | 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 | 17,906,000 | 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 | 11,132,000 | 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 | 1,920,000 | 2,209,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 306,539,000 | 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 | 211,563,000 | 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 | 92,583,000 | 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 | 2,393,000 | 17,979,000 |
Commercial Portfolio Segment [Member] | Originated Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 505,715,000 | 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 | 378,741,000 | 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 | 121,241,000 | 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 | 5,733,000 | 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 | 36,762,000 | 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 | 18,842,000 | 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 | 16,868,000 | 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 | 1,052,000 | 1,382,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 475,300,000 | 562,114,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Commercial and Industrial [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 120,772,000 | 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 | 67,167,000 | 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 | 50,573,000 | 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 | 3,032,000 | 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 | 16,776,000 | 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 | 4,918,000 | 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 | 11,028,000 | 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 | 830,000 | 1,801,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 120,477,000 | 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 | 46,693,000 | 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 | 68,194,000 | 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 | 5,590,000 | 6,922,000 |
Commercial Portfolio Segment [Member] | Acquired Loan [Member] | Real Estate Non Owner Occupied Loan [Member] |  |  |
Financing Receivable, Recorded Investment [Line Items] |  |  |
Loans | 130,512,000 | 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 | 70,884,000 | 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 | 57,262,000 | 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 | 2,366,000 | 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 | 86,763,000 | 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 | 46,299,000 | 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 | 37,162,000 | 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 | $ 3,302,000 | $ 1,063,000 |

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