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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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Number of loans as on closing date.

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Percentage of government guarantee for loans as per scheme.

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