Note 6 - Goodwill and Other Intangible Assets (Details) - Goodwill and Other Intangibles (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Note 6 - Goodwill and Other Intangible Assets (Details) - Goodwill and Other Intangibles [Line Items]
Goodwill	$ 314,643us-gaap_Goodwill	$ 108,095us-gaap_Goodwill
Core deposit premiums:
Total goodwill and other intangible assets	362,530	130,621
Core Deposit Premium [Member]
Core deposit premiums:
Gross carrying amount	44,030	18,318
Accumulated amortization	(2,939)	(2,386)
Net carrying amount	41,091	15,932
Purchased Credit Card Relationships [Member]
Core deposit premiums:
Gross carrying amount	2,068	2,068
Accumulated amortization	(621)	(517)
Net carrying amount	1,447	1,551
Books of Business Intangible [Member]
Core deposit premiums:
Gross carrying amount	5,560	5,140
Accumulated amortization	(211)	(97)
Net carrying amount	5,349	5,043
Other Intangible Assets [Member]
Core deposit premiums:
Net carrying amount	$ 47,887	$ 22,526

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

Carrying amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance.

+ References

No definition available.

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