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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 | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2025 USD ($) yr mo | Jun. 30, 2024 USD ($) yr mo | Dec. 31, 2024 USD ($)
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |  |
Mortgage servicing rights |  | $ 1,491 | $ 1,452
State and political subdivisions | $ 1,748 | $ 2,057 |
Discount Rate [Member] |  |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |  |
Mortgage servicing rights, measurement input | 9.5 |  |
Discount Rate [Member] | Discounted Cash Flow [Member] |  |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |  |
Mortgage servicing rights, measurement input |  | 10 |
Constant Prepayment Rate [Member] | Discounted Cash Flow [Member] |  |  |
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] |  |  |
Mortgage servicing rights, measurement input |  | 8 |
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 | 6.2 | 6.2 |
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 | 0.08 | 0.08 |
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 | 8.6 |  |
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 | 7 | 7 |
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 | 8.2 | 7.7 |
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 | 0.11 | 0.11 |
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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