Other Borrowings - Contractual Maturities of FHLB Long-term Advances (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Sep. 30, 2016
Federal Home Loan Bank Advances [Line Items]
Advances from Federal Home Loan Banks	$ 174,168	$ 230,601
Convertible [Member]
Federal Home Loan Bank Advances [Line Items]
Maturity Range From	2018
Maturity Range To	2018
Advances from Federal Home Loan Banks	$ 5,000	5,000
Convertible [Member] \| Weighted-Average [Member]
Federal Home Loan Bank Advances [Line Items]
Interest Rate	3.30%
Convertible [Member] \| Minimum [Member]
Federal Home Loan Bank Advances [Line Items]
Interest Rate	3.30%
Convertible [Member] \| Maximum [Member]
Federal Home Loan Bank Advances [Line Items]
Interest Rate	3.30%
Fixed Rate [Member]
Federal Home Loan Bank Advances [Line Items]
Maturity Range From	2017
Maturity Range To	2020
Advances from Federal Home Loan Banks	$ 75,601	98,851
Fixed Rate [Member] \| Weighted-Average [Member]
Federal Home Loan Bank Advances [Line Items]
Interest Rate	1.68%
Fixed Rate [Member] \| Minimum [Member]
Federal Home Loan Bank Advances [Line Items]
Interest Rate	0.89%
Fixed Rate [Member] \| Maximum [Member]
Federal Home Loan Bank Advances [Line Items]
Interest Rate	2.85%
Mid-Term [Member]
Federal Home Loan Bank Advances [Line Items]
Maturity Range From	2017
Maturity Range To	2019
Advances from Federal Home Loan Banks	$ 93,567	$ 126,750
Mid-Term [Member] \| Weighted-Average [Member]
Federal Home Loan Bank Advances [Line Items]
Interest Rate	1.29%
Mid-Term [Member] \| Minimum [Member]
Federal Home Loan Bank Advances [Line Items]
Interest Rate	0.76%
Mid-Term [Member] \| Maximum [Member]
Federal Home Loan Bank Advances [Line Items]
Interest Rate	1.66%

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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- Definition

The earliest year of maturity for the advances from the Federal Home Loan Bank as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

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- Definition

The last year of maturity for the advances from the Federal Home Loan Bank as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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- Definition

States the interest rate applicable to Federal Home Loan Bank advances outstanding as of the Balance Sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

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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.

+ Details

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