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Loans and Allowance for Loan Losses- Additional Information (Detail) | 6 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2022 USD ($) SecurityLoan Loans | Dec. 31, 2021 USD ($) Loans | Jun. 30, 2022 USD ($) Loans 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
Investment recorded prior to modification | $ 0 | $ 0 | $ 0
Loans and Leases Receivable, Gross | 568,240,000 | 498,111,000 | 525,736,000
Fair Value, Concentration of Risk, Collateral Policy [Member] |  |  |
Loans and Allowance for Credit Losses [Line Items] |  |  |
Commercial and multi-family real estate | $ 322,406,000 |  | 290,972,000
Troubled Debt Restructurings [Member] |  |  |
Loans and Allowance for Credit Losses [Line Items] |  |  |
Minimum period for default | 90 days |  |
Commercial Business Loans [Member] |  |  |
Loans and Allowance for Credit Losses [Line Items] |  |  |
Loans and Leases Receivable, Gross | $ 72,360,000 | $ 80,403,000 | $ 80,418,000
Commercial Business Loans [Member] | Small Business Administration Paycheck Protection Programme Loans [Member] |  |  |
Loans and Allowance for Credit Losses [Line Items] |  |  |
Percentage of government guarantee for loans as per scheme | 100.00% |  |
Commercial Portfolio And Commercial Residential Portfolio [Member] |  |  |
Loans and Allowance for Credit Losses [Line Items] |  |  |
Number of loans as on closing date | Loans | 0 | 43 | 0
Loans and Leases Receivable, Gross |  | $ 8,000,000 |
One- to four-family [Member] |  |  |
Loans and Allowance for Credit Losses [Line Items] |  |  |
Loans held for sale | $ 0 |  | $ 227,000
Maximum term of fixed-rate one- to four-family residential mortgage loans | 15 years |  |
Loans and Leases Receivable, Gross | $ 150,711,000 | $ 125,406,000 | 132,474,000
Purchased Loans and Loan Participations [Member] |  |  |
Loans and Allowance for Credit Losses [Line Items] |  |  |
Approximate amount of purchase loans included in loans receivable | 696,000 |  | 1,570,000
Approximate amount of loans included on out-of-area participation | 38,589,000 |  | 29,972,000
Amount within 100 miles of primary area | $ 21,551,000 |  | $ 13,234,000
Non troubled debt restructuring [Member] | Covid Nineteen [Member] | Financing receivables, 30 to 59 days past due [Member] |  |  |
Loans and Allowance for Credit Losses [Line Items] |  |  |
Financing receivable number of days past due | 30 days |  |
Period of loan excecution | 60 days |  |

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