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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) | 6 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2022 USD ($) yr | Jun. 30, 2022 USD ($) $ / pure mo yr
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Mortgage servicing rights | $ 1,515,000 | $ 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 | 0.1 | 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 | 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 | 6.8 | 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 | 0.14 | 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 | 6.6 | 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 | 3.03 | 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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