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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)	12 Months Ended
	Jun. 30, 2023 USD ($) yr mo	Jun. 30, 2022 USD ($) mo yr
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Mortgage servicing rights	$ 1,482,000	$ 1,463,000
Impaired loans (collateral dependent)	$ 2,361,000	$ 2,662,000
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
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	6	6
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	0.09	0.1
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	7	6.7
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	0.14
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	9	10
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] | 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
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	6.9	6.7
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	3.03
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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