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-Publisher FASB

-Name Accounting Standards Codification

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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.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Note 6 - Goodwill and Other Intangible Assets (Details) (USD $)	3 Months Ended		0 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Sep. 30, 2013	Dec. 31, 2014	Feb. 27, 2015
Note 6 - Goodwill and Other Intangible Assets (Details) [Line Items]
Goodwill	$ 314,643,000us-gaap_Goodwill			$ 108,095,000us-gaap_Goodwill
Core Deposit Premium [Member] \| Community First Bancshares, Inc. [Member]
Note 6 - Goodwill and Other Intangible Assets (Details) [Line Items]
Finite-lived Intangible Assets Acquired	11,300,000
Core Deposit Premium [Member] \| Liberty Bancshares, Inc. [Member]
Note 6 - Goodwill and Other Intangible Assets (Details) [Line Items]
Finite-lived Intangible Assets Acquired	14,600,000
Core Deposit Premium [Member]
Note 6 - Goodwill and Other Intangible Assets (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Amortization of Intangible Assets	350,000,000,000	670,000
Books of Business Intangible [Member] \| Community First Bancshares, Inc. [Member]
Note 6 - Goodwill and Other Intangible Assets (Details) [Line Items]
Finite-lived Intangible Assets Acquired	400,000
Books of Business Intangible [Member] \| Delta Acquisition [Member]
Note 6 - Goodwill and Other Intangible Assets (Details) [Line Items]
Finite-lived Intangible Assets Acquired	5,100,000
Books of Business Intangible [Member] \| Minimum [Member]
Note 6 - Goodwill and Other Intangible Assets (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	10 years
Books of Business Intangible [Member] \| Maximum [Member]
Note 6 - Goodwill and Other Intangible Assets (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life	15 years
Books of Business Intangible [Member]
Note 6 - Goodwill and Other Intangible Assets (Details) [Line Items]
Amortization of Intangible Assets	120,000	0
Purchased Credit Card Relationships [Member]
Note 6 - Goodwill and Other Intangible Assets (Details) [Line Items]
Finite-Lived Intangible Asset, Useful Life			5 years
Finite-lived Intangible Assets Acquired			2,100,000
Amortization of Intangible Assets	103,000	103,000
Community First Bancshares, Inc. [Member]
Note 6 - Goodwill and Other Intangible Assets (Details) [Line Items]
Goodwill					111,600,000
Goodwill, Acquired During Period	94,900,000
Liberty Bancshares, Inc. [Member]
Note 6 - Goodwill and Other Intangible Assets (Details) [Line Items]
Goodwill					94,912,000
Goodwill, Acquired During Period	$ 111,600,000