Note 5 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014
Note 5 - Loans and Allowance for Credit Losses (Details) - Recorded Investment in Loans by Impairment Method [Line Items]
Individually evaluated for impairment	$ 43,321	$ 45,310	$ 57,246
Collectively evaluated for impairment	4,410,614	4,267,089	3,006,729
Ending balance	4,444,893	4,312,399	3,063,975
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	16,981	17,612	27,327
Collectively evaluated for impairment	919,493	898,614	677,059
Ending balance	933,715	916,226	704,386
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	4,601	5,109	2,508
Collectively evaluated for impairment	1,737,174	1,698,063	1,193,897
Ending balance	1,739,483	1,703,172	1,196,405
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	6,840	6,891	7,323
Collectively evaluated for impairment	490,154	454,690	313,671
Ending balance	493,003	461,581	320,994
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	147,871	148,018	97,733
Ending balance	147,871	148,018	97,846
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	889	1,398	756
Collectively evaluated for impairment	119,654	121,138	108,083
Ending balance	120,543	122,536	108,839
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	10	59	60
Collectively evaluated for impairment	98,697	109,343	5,998
Ending balance	98,707	109,402	6,058
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	14,000	14,241	19,159
Collectively evaluated for impairment	897,571	837,223	610,288
Ending balance	$ 911,571	$ 851,464	$ 629,447

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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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