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Loans and Allowance for Credit Losses - Additional Information (Detail) | 6 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2023 USD ($) SecurityLoan | Jun. 30, 2023 USD ($) 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
Foreclosed residential real estate properties | $ 7,000 | $ 31,000
Fair Value, Concentration of Risk, Collateral Policy [Member] |  |
Loans and Allowance for Credit Losses [Line Items] |  |
Commercial and multi-family real estate | $ 369,596,000 | 328,721,000
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 |
One- to four-family [Member] |  |
Loans and Allowance for Credit Losses [Line Items] |  |
Loans held for sale | $ 689,000 | 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 | $ 605,000 | 652,000
Approximate amount of loans included on out-of-area participation | 47,075,000 | 46,073,000
Amount within 100 miles of primary area | $ 30,338,000 | $ 28,951,000

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