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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)

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

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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

-Publisher FASB

-Name Accounting Standards Codification

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Intangible Assets - Summary of Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Schedule Of Intangible Assets [Line Items]
Gross Carrying Amount	$ 19,864
Accumulated Amortization	(9,231)
Net Carrying Amount	10,633	12,083	12,630
Core deposit intangibles [Member]
Schedule Of Intangible Assets [Line Items]
Gross Carrying Amount	13,473
Accumulated Amortization	(6,845)
Net Carrying Amount	6,628
Customer relationship intangibles [Member]
Schedule Of Intangible Assets [Line Items]
Gross Carrying Amount	5,657
Accumulated Amortization	(2,247)
Net Carrying Amount	3,410
Mortgage Servicing Intangibles [Member]
Schedule Of Intangible Assets [Line Items]
Gross Carrying Amount	734
Accumulated Amortization	(139)
Net Carrying Amount	$ 595