Goodwill and Intangible Assets - Schedule of Acquired Intangible Assets (Detail) - Core Deposit and Other Intangibles [Member] - USD ($) $ in Thousands	Sep. 30, 2015	Sep. 30, 2014
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 7,274	$ 9,378
Accumulated Amortization	$ 5,264	$ 7,689

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

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

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