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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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