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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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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 310



-SubTopic 10



-Section 45



-Paragraph 2



-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522



Reference 2: http://www.xbrl.org/2003/role/presentationRef



-Publisher FASB



-Name Accounting Standards Codification



-Topic 310



-SubTopic 10



-Section 50



-Paragraph 4



-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5074-111524

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