Accounting for Certain Loans Acquired with Deteriorated Credit Quality - Schedule of Impaired Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	$ 160,379	$ 193,864
Recorded Investment	70,845	92,595
Carrying Value	69,640	91,602
Commercial real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	100,761	110,797
Recorded Investment	27,001	30,099
Carrying Value	26,322	29,417
Agriculture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	4,841	10,463
Recorded Investment	2,815	7,174
Carrying Value	2,551	7,059
Commercial non-real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	7,475	9,825
Recorded Investment	416	1,920
Carrying Value	416	1,920
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	46,646	61,981
Recorded Investment	40,025	52,736
Carrying Value	39,763	52,540
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding Balance	656	798
Recorded Investment	588	666
Carrying Value	$ 588	$ 666

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82894507&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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544

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