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Loans and Allowance for Credit Losses - Additional Information (Detail) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 USD ($) SecurityLoan | Jun. 30, 2024 USD ($) SecurityLoan
Loans and Allowance for Credit Losses [Line Items] |  |
Maximum term of fixed-rate one- to four-family residential mortgage loans | 15 years |
Number of default loans | SecurityLoan | 0 | 0
Fair Value, Concentration of Risk, Collateral Policy [Member] |  |
Loans and Allowance for Credit Losses [Line Items] |  |
Commercial and multi-family real estate | $ 349,133,000 | $ 346,499,000
Troubled Debt Restructurings [Member] |  |
Loans and Allowance for Credit Losses [Line Items] |  |
Minimum period for default | 90 days |
Residential Real Estate [Member] |  |
Loans and Allowance for Credit Losses [Line Items] |  |
Foreclosed residential real estate properties | $ 0 | 0
One- to four-family [Member] |  |
Loans and Allowance for Credit Losses [Line Items] |  |
Loans held for sale | $ 0 | 0
Maximum term of fixed-rate one- to four-family residential mortgage loans | 15 years |
Purchased Loans and Loan Participations [Member] |  |
Loans and Allowance for Credit Losses [Line Items] |  |
Approximate amount of purchase loans included in loans receivable | $ 237,000 | 253,000
Approximate amount of loans included on out-of-area participation | 54,082,000 | 51,798,000
Amount within 100 miles of primary area | $ 37,297,000 | $ 34,929,000

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