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Business Combinations Estimated Fair Values Of Assets Acquired And Liabilities Assumed (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Sep. 10, 2010 First Bank [Member]	Sep. 10, 2010 Acquired Book Value [Member] First Bank [Member]	Sep. 10, 2010 Fair Value Adjustments [Member] First Bank [Member]
Assets
Cash			$ 180,074	$ 180,074	$ 0
Loans			133,117	135,219	(2,102)
Premises and equipment			12,951	5,266	7,685
Goodwill	25,753	25,753	8,390	0	8,390
Core deposit intangible			3,050	0	3,050
Other assets			488	488	0
Total assets acquired			338,070	321,047	17,023
Liabilities
Deposits			337,429	336,016	1,413
Securities sold under agreements to repurchase			126	126	0
Other liabilities			515	515	0
Total liabilities assumed			$ 338,070	$ 336,657	$ 1,413

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The amount of identifiable intangible assets recognized as of the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

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