Note 5 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Note 5 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	$ 45,310	$ 34,597
Collectively evaluated for impairment	4,267,089	2,910,561
Ending balance	4,312,399	2,945,158
Commercial Loan [Member]
Note 5 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	17,612	9,614
Collectively evaluated for impairment	898,614	684,736
Ending balance	916,226	694,350
Commercial Real Estate Investment [Member]
Note 5 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	5,109	2,682
Collectively evaluated for impairment	1,698,063	1,117,118
Ending balance	1,703,172	1,119,800
Commercial Real Estate Owner Occupied [Member]
Note 5 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	6,891	7,574
Collectively evaluated for impairment	454,690	309,917
Ending balance	461,581	317,491
Residential Mortgage [Member]
Note 5 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment		113
Collectively evaluated for impairment	148,018	90,305
Ending balance	148,018	90,418
Home Equity Line of Credit [Member]
Note 5 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	1,398	682
Collectively evaluated for impairment	121,138	109,560
Ending balance	122,536	110,242
Consumer, Other [Member]
Note 5 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	59	70
Collectively evaluated for impairment	109,343	3,961
Ending balance	109,402	4,031
Construction Loans [Member]
Note 5 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	14,241	13,862
Collectively evaluated for impairment	837,223	594,964
Ending balance	$ 851,464	$ 608,826

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The balance of financing receivables that were collectively evaluated for impairment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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The balance of financing receivables that were individually evaluated for impairment.

+ References

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- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: 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=35738203&loc=d3e5074-111524

Reference 2: 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

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