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	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2019
Real estate loans
Total loans	$ 511,318		$ 515,887	$ 500,682
Unearned fees and discounts, net	513		(164)
Allowance for loan losses	6,351	$ 6,449	6,234	6,474	$ 6,222	$ 6,328
Loans, net	504,454		509,817
One- to four-family [Member]
Real estate loans
Total loans	116,363		128,876	129,185
Allowance for loan losses	955	1,011	1,044	1,038	991	1,031
Multi-family [Member]
Real estate loans
Total loans	105,895		96,195	107,107
Allowance for loan losses	1,741	1,744	1,514	1,683	1,562	1,642
Home equity lines of credit [Member]
Real estate loans
Total loans	7,814		8,551	9,131
Allowance for loan losses	79	79	87	92	90	89
Construction [Member]
Real estate loans
Total loans	20,783		22,042	20,897
Allowance for loan losses	199	130	240	244	217	213
Commercial [Member]
Real estate loans
Total loans	149,639		145,113	143,396
Allowance for loan losses	1,758	1,782	1,706	1,680	1,685	1,623
Commercial [Member]
Real estate loans
Total loans	103,326		107,581	83,812
Allowance for loan losses	1,560	1,636	1,583	1,667	1,610	1,659
Consumer [Member]
Real estate loans
Total loans	7,498		7,529	7,154
Allowance for loan losses	$ 59	$ 67	$ 60	$ 70	$ 67	$ 71