Loans - Subsequent Defaults on Modified Loans (Details) $ in Thousands	12 Months Ended
Sep. 30, 2016 USD ($) contract	Sep. 30, 2015 USD ($) contract	Sep. 30, 2014 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Loans \| contract	6	5	22
Recorded Investment \| $	$ 7,590	$ 8	$ 1,667
Residential real estate
Financing Receivable, Modifications [Line Items]
Number of Loans \| contract	1	1	11
Recorded Investment \| $	$ 0	$ 8	$ 419
Commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Loans \| contract	0	0	0
Recorded Investment \| $	$ 0	$ 0	$ 0
Commercial non real estate
Financing Receivable, Modifications [Line Items]
Number of Loans \| contract	2	2	8
Recorded Investment \| $	$ 275	$ 0	$ 313
Agriculture
Financing Receivable, Modifications [Line Items]
Number of Loans \| contract	2	0	2
Recorded Investment \| $	$ 7,307	$ 0	$ 935
Consumer
Financing Receivable, Modifications [Line Items]
Number of Loans \| contract	1	2	1
Recorded Investment \| $	$ 8	$ 0	$ 0

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953682-111524

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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