Disclosures about Fair Value of Assets - Quantitative Information about Unobservable Inputs Used in Recurring and Nonrecurring Level 3 Fair Value Measurements (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2016	Jun. 30, 2016
Mortgage Servicing Rights [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Valuation Technique	Discounted cash flow
Fair Value	$ 518	$ 440
Mortgage Servicing Rights [Member] \| Minimum [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unobservable Input, Discount rate	9.50%	9.50%
Unobservable Inputs, Constant prepayment rate	12.80%	12.80%
Unobservable Inputs, Probability of default	0.06%	0.06%
Mortgage Servicing Rights [Member] \| Maximum [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unobservable Input, Discount rate	10.50%	10.50%
Unobservable Inputs, Constant prepayment rate	13.50%	13.40%
Unobservable Inputs, Probability of default	0.32%	0.32%
Mortgage Servicing Rights [Member] \| Weighted Average [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unobservable Input, Discount rate	9.50%	9.50%
Unobservable Inputs, Constant prepayment rate	13.50%	13.30%
Unobservable Inputs, Probability of default	0.31%	0.31%
Impaired Loans (Collateral Dependent) [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Valuation Technique	Market comparable properties
Fair Value	$ 440	$ 108
Unobservable Inputs, Marketability discount		11.80%
Impaired Loans (Collateral Dependent) [Member] \| Weighted Average [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unobservable Inputs, Marketability discount		11.80%

Adjustment to the discount rate used to measure fair value for lack of ability to convert business interests into cash quickly.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

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Rate at which loans or a loan portfolio are expected to prepay principal balances, used as an input to measure fair value.

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Percentage of likelihood a loan will not be repaid and instead default, used as an input to measure fair value.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Description of the inputs and valuation technique(s) used to measure fair value.

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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.

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No definition available.

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