Fair Value Measurements - Summary of Mortgage Loans Held-For-Sale, Fair Value Measurement (Details) - Fair value, measurements, nonrecurring - USD ($) $ in Thousands	Jun. 30, 2017	Sep. 30, 2016
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Other real estate owned	$ 3,985	$ 6,911
Impaired loans	203,786	190,743
Loans held for sale, at lower of cost or fair value	11,504	12,918
Loan servicing rights	4,530	5,781
Property held for sale	5,074	8,112
Level 1
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Other real estate owned	0	0
Impaired loans	0	0
Loans held for sale, at lower of cost or fair value	0	0
Loan servicing rights	0	0
Property held for sale	0	0
Level 2
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Other real estate owned	0	0
Impaired loans	0	0
Loans held for sale, at lower of cost or fair value	11,504	12,918
Loan servicing rights	0	0
Property held for sale	0	0
Level 3
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Other real estate owned	3,985	6,911
Impaired loans	203,786	190,743
Loans held for sale, at lower of cost or fair value	0	0
Loan servicing rights	4,530	5,781
Property held for sale	$ 5,074	$ 8,112

Impaired Loans Receivable, Fair Value Disclosure

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Real Estate Acquired Through Foreclosure, Fair Value Disclosure

+ References

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- Definition

Fair value portion of assets classified as held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19190-110258

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=68078379&loc=d3e122625-111746

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