Goodwill and Other Intangible Assets - Estimated Future Amortization Expense (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014
Loan Servicing Rights [Member]
Finite-Lived Intangible Assets [Line Items]
2014	$ 4,994
2015	5,223
2016	4,039
2017	3,142
2018	2,382
Core Deposits [Member]
Finite-Lived Intangible Assets [Line Items]
2014	1,674
2015	1,758
2016	1,195
2017	815
2018	610
Other [Member]
Finite-Lived Intangible Assets [Line Items]
2014	346
2015	434
2016	233
2017	220
2018	$ 193

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.

+ References

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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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