Accounting for Certain Loans Acquired with Deteriorated Credit Quality - Schedule of Impaired Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Sep. 30, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	$ 210,711	$ 238,106
Recorded Investment	106,763	129,531
Carrying Value	106,105	127,852
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	66,140	76,696
Recorded Investment	56,492	65,737
Carrying Value	56,492	64,830
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	120,999	129,615
Recorded Investment	38,221	44,448
Carrying Value	37,563	43,676
Commercial non real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	10,355	11,588
Recorded Investment	2,393	3,196
Carrying Value	2,393	3,196
Agriculture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	12,386	19,174
Recorded Investment	8,963	15,254
Carrying Value	8,963	15,254
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	831	1,033
Recorded Investment	694	896
Carrying Value	$ 694	$ 896

Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Recorded Investment

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- Definition

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.

+ References

No definition available.

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- Definition

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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- Definition

The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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