Derivatives and Hedging Activities (Details) (USD $)	6 Months Ended
Mar. 31, 2015	Sep. 30, 2014
Interest rate swap agreements
Derivative [Line Items]
Notional amount	$ 158,421,000	$ 264,169,000
Gain (loss) on derivative instruments	0
Fee income included in miscellaneous loan fees	754,897
Other assets \| Interest rate contracts
Derivative [Line Items]
Asset derivatives, fair value	8,562,000	2,879,000
Other liabilities \| Interest rate contracts
Derivative [Line Items]
Liability derivatives, fair value	8,562,000	2,879,000
Forward Contracts [Member] \| Interest rate swap agreements
Derivative [Line Items]
Notional amount	300,000,000
Gain (loss) recognized in other comprehensive income (loss), effective portion, net	(6,010,354)
Forward Contracts [Member] \| Other assets \| Interest rate contracts
Derivative [Line Items]
Asset derivatives, fair value	0	0
Forward Contracts [Member] \| Other liabilities \| Interest rate contracts
Derivative [Line Items]
Liability derivatives, fair value	$ 9,503,000	$ 0

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset against an obligation to return collateral under a master netting arrangement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=20225523&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41678-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226011-175313

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=28370219&loc=SL20226006-175313

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Fair value of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset against a right to receive collateral under a master netting arrangement.

+ References

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959

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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

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+ References

No definition available.

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