Mergers and Acquisitions Purchase Price and Goodwill Recognized (Details 1) (Wheatland Bankshares [Member], USD $)	May 31, 2013
Wheatland Bankshares [Member]
Purchase price
Fair value of Company common stock shares issued	$ 28,290,000
Cash consideration for outstanding shares	11,025,000
Total purchase price	39,315,000
Fair value of net assets acquired
Tangible assets acquired	285,053,000
Core deposit intangible asset acquired	2,079,000
Liabilities assumed	(261,226,000)
Total fair value of net assets acquired	25,906,000
Goodwill recognized	$ 13,409,000

Business acquisition purchase price allocation net assets.

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Amount of cash paid to acquire the entity.

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The acquisition-date fair value of the equity interests of the acquirer, including the number of instruments or interests issued or issuable in consideration for the business combination.

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The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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Amount of acquisition cost of a business combination allocated to assets, excluding financial assets and goodwill, lacking physical substance.

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The amount of acquisition cost of a business combination allocated to liabilities assumed.

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The amount of acquisition cost of a business combination allocated to tangible assets.

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