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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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Loans Receivable - Summary of Loans Receivable (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2020
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable, before fees	$ 1,294,081		$ 1,237,522
Loans receivable	1,294,597		1,237,332
Allowance for loan losses	(8,711)	$ (8,429)	(7,881)	$ (7,865)	$ (8,677)	$ (8,639)
Loans receivable, net	1,285,886		1,229,451
Residential [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable, before fees	215,431		224,305
Commercial [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable, before fees	897,424		826,624
Construction [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable, before fees	16,894		10,151
Allowance for loan losses	(166)	(129)	(102)	(102)	(205)	(165)
Commercial Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable, before fees	141,427		150,658
Allowance for loan losses	(1,109)	(1,067)	(948)	(848)	(1,201)	(1,124)
Home Equity Lines Of Credit [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable, before fees	22,557		25,439
Allowance for loan losses	(49)	(51)	(54)	(62)	(61)	$ (60)
Consumer and Overdrafts [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans receivable, before fees	348		345
Allowance for loan losses	(4)	$ (10)	(5)	$ (3)	$ (4)
Mortgage Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Net deferred loan origination (fees) costs	(23)		196
Loans receivable	1,129,726		1,061,276
Commercial and Consumer Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Net deferred loan origination (fees) costs	539		(386)
Loans receivable	$ 164,871		$ 176,056