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Disclosures About Fair Value of Assets - Quantitative Information about Unobservable Inputs Used in Recurring and Nonrecurring Level 3 Fair Value Measurements (Detail) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2025 USD ($) mo yr	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) mo yr
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights	$ 1,430		$ 1,429
State and political subdivisions	1,748	$ 1,748
Foreclosed assets	$ 40
Discount Rate [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	9.5		9.5
Comparability Adjustments [Member] | Market Comparable Properties [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0
Minimum [Member] | Constant Prepayment Rate [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	5		4.9
Minimum [Member] | Probability of Default [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0.07		0.07
Minimum [Member] | Maturity/Call Date [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input | mo	1		1
Minimum [Member] | Weighted average coupon [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	2.97		2.97
Minimum [Member] | Marketability yield adjustment [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	1		1
Maximum [Member] | Constant Prepayment Rate [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	11.1		9.8
Maximum [Member] | Probability of Default [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0.12		0.12
Maximum [Member] | Maturity/Call Date [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input | yr	6		6
Maximum [Member] | Weighted average coupon [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	3.08		3.08
Maximum [Member] | Marketability yield adjustment [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	2		2
Weighted Average [Member] | Constant Prepayment Rate [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	10.3		9.2
Weighted Average [Member] | Probability of Default [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	0.12		0.12
Weighted Average [Member] | Weighted average coupon [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	3.04		3.04
Weighted Average [Member] | Marketability yield adjustment [Member] | Discounted Cash Flow [Member]
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights, measurement input	1.6		1.6

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 825
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478898/942-825-50-1

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