Note 4 - Loans and Allowance for Loan Losses (Details) - Recorded Investment in Loans, Excluding Loans Acquired - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Note 4 - Loans and Allowance for Loan Losses (Details) - Recorded Investment in Loans, Excluding Loans Acquired [Line Items]
Balance, end of period	$ 4,853,094	$ 2,736,634
Commercial Portfolio Segment [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Recorded Investment in Loans, Excluding Loans Acquired [Line Items]
Balance, end of period	564,679	407,478
Commercial Real Estate Portfolio Segment [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Recorded Investment in Loans, Excluding Loans Acquired [Line Items]
Balance, end of period	1,914,409	1,352,328
Consumer Portfolio Segment [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Recorded Investment in Loans, Excluding Loans Acquired [Line Items]
Balance, end of period	354,173	288,782
Unallocated Financing Receivables [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Recorded Investment in Loans, Excluding Loans Acquired [Line Items]
Balance, end of period	6,017	5,133
Loans, Excluding Acquired Loans [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Recorded Investment in Loans, Excluding Loans Acquired [Line Items]
Loans individually evaluated for impairment	17,244	14,669
Loans collectively evaluated for impairment	2,822,034	2,039,052
Balance, end of period	2,839,278	2,053,721
Loans, Excluding Acquired Loans [Member] \| Commercial Portfolio Segment [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Recorded Investment in Loans, Excluding Loans Acquired [Line Items]
Loans individually evaluated for impairment	2,236	1,026
Loans collectively evaluated for impairment	562,443	406,452
Balance, end of period	564,679	407,478
Loans, Excluding Acquired Loans [Member] \| Commercial Real Estate Portfolio Segment [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Recorded Investment in Loans, Excluding Loans Acquired [Line Items]
Loans individually evaluated for impairment	13,875	12,827
Loans collectively evaluated for impairment	1,900,534	1,339,501
Balance, end of period	1,914,409	1,352,328
Loans, Excluding Acquired Loans [Member] \| Consumer Portfolio Segment [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Recorded Investment in Loans, Excluding Loans Acquired [Line Items]
Loans individually evaluated for impairment	461	197
Loans collectively evaluated for impairment	171,240	185,183
Balance, end of period	171,701	185,380
Loans, Excluding Acquired Loans [Member] \| Unallocated Financing Receivables [Member]
Note 4 - Loans and Allowance for Loan Losses (Details) - Recorded Investment in Loans, Excluding Loans Acquired [Line Items]
Loans individually evaluated for impairment	672	619
Loans collectively evaluated for impairment	187,817	107,916
Balance, end of period	$ 188,489	$ 108,535

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- Definition

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=49124121&loc=SL6953423-111524

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

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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 45

-Paragraph 2

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

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-Name Accounting Standards Codification

-Topic 310

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-Section 50

-Paragraph 4

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