Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Loans and Allowance for Loan Losses - Categories of Loans (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021
Real estate loans
Total loans	$ 568,240		$ 525,736	$ 498,111
Unearned fees and discounts, net	(201)		(247)
Allowance for loan losses	7,166	$ 7,023	7,052	6,395	$ 6,470	$ 6,599
Loans, net	561,275		518,931
One- to four-family [Member]
Real estate loans
Total loans	150,711		132,474	125,406
Allowance for loan losses	1,722	1,537	1,028	1,082	974	967
Multi-family [Member]
Real estate loans
Total loans	100,147		88,247	86,790
Allowance for loan losses	1,402	1,284	1,375	1,400	1,562	1,674
Home equity lines of credit [Member]
Real estate loans
Total loans	6,926		6,987	6,168
Allowance for loan losses	101	94	70	62	63	67
Construction [Member]
Real estate loans
Total loans	36,595		41,254	26,474
Allowance for loan losses	585	549	489	299	321	258
Commercial [Member]
Real estate loans
Total loans	192,015		167,375	164,879
Allowance for loan losses	2,392	2,386	1,985	1,962	1,916	1,831
Commercial [Member]
Real estate loans
Total loans	72,360		80,418	80,403
Allowance for loan losses	871	1,090	2,025	1,521	1,571	1,740
Consumer [Member]
Real estate loans
Total loans	9,486		8,981	7,991
Allowance for loan losses	$ 93	$ 83	$ 80	$ 69	$ 63	$ 62