Intangible Assets - Summary of Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013
Schedule Of Intangible Assets [Line Items]
Gross Carrying Amount	$ 19,895
Accumulated Amortization	(8,795)
Net Carrying Amount	11,100
Core deposit intangibles [Member]
Schedule Of Intangible Assets [Line Items]
Gross Carrying Amount	13,473
Accumulated Amortization	(6,508)
Net Carrying Amount	6,965
Customer relationship intangibles [Member]
Schedule Of Intangible Assets [Line Items]
Gross Carrying Amount	5,657
Accumulated Amortization	(2,160)
Net Carrying Amount	3,497
Mortgage Servicing Intangibles [Member]
Schedule Of Intangible Assets [Line Items]
Gross Carrying Amount	765
Accumulated Amortization	(127)
Net Carrying Amount	$ 638

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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)

-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

+ Details

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- Definition

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

+ References

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