Goodwill and Other Intangible Assets - Estimated Future Amortization Expense (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013
Loan servicing rights [Member]
Finite-Lived Intangible Assets [Line Items]
2013	$ 3,064
2014	6,343
2015	4,929
2016	3,782
2017	2,921
Core deposits [Member]
Finite-Lived Intangible Assets [Line Items]
2013	1,432
2014	2,359
2015	1,758
2016	1,195
2017	815
Other [Member]
Finite-Lived Intangible Assets [Line Items]
2013	245
2014	466
2015	434
2016	233
2017	$ 220

Amount of amortization expense expected to be recognized during the next fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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)(3)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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Amount of amortization expense expected to be recognized in the remainder of the fiscal year following the latest fiscal year ended for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

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- Definition

Amount of amortization expense expected to be recognized during the fourth fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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Amount of amortization expense expected to be recognized during the third fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of amortization expense expected to be recognized during the second fiscal year following the latest fiscal year for assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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