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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) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2023 USD ($) yr mo | Jun. 30, 2023 USD ($) mo yr
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |
Mortgage servicing rights | $ 1,410,000 | $ 1,482,000
State and political subdivision | $ 2,058,000 | $ 2,361,000
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 | 6.1 | 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 | 0.09
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 | 7.5 | 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 | 0.12
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 | 8 | 9
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 | 7.2 | 6.9
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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