Loans Receivable - Summary of Activity in Allowance for Loan Losses by Portfolio Segment (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
Loans and Leases Receivable Disclosure [Line Items]
Allowance for Loan Losses, Beginning Allowance	$ 8,429	$ 8,677	$ 7,881	$ 8,639
Allowance for Loan Losses, Provision (benefit)	286	(894)	563	(678)
Allowance for Loan Losses, Charge-offs	(24)	(27)	(142)	(268)
Allowance for Loan Losses, Recoveries	20	109	409	172
Allowance for Loan Losses, Ending Allowance	8,711	7,865	8,711	7,865
Residential Mortgages [Member]
Loans and Leases Receivable Disclosure [Line Items]
Allowance for Loan Losses, Beginning Allowance	319	334	337	373
Allowance for Loan Losses, Provision (benefit)	1	(4)	(21)	(49)
Allowance for Loan Losses, Recoveries	4	2	8	8
Allowance for Loan Losses, Ending Allowance	324	332	324	332
Commercial Mortgages [Member]
Loans and Leases Receivable Disclosure [Line Items]
Allowance for Loan Losses, Beginning Allowance	6,853	6,872	6,435	6,913
Allowance for Loan Losses, Provision (benefit)	206	(354)	624	(395)
Allowance for Loan Losses, Ending Allowance	7,059	6,518	7,059	6,518
Construction [Member]
Loans and Leases Receivable Disclosure [Line Items]
Allowance for Loan Losses, Beginning Allowance	129	205	102	165
Allowance for Loan Losses, Provision (benefit)	37	(103)	64	(63)
Allowance for Loan Losses, Ending Allowance	166	102	166	102
Commercial Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Allowance for Loan Losses, Beginning Allowance	1,067	1,201	948	1,124
Allowance for Loan Losses, Provision (benefit)	40	(437)	(121)	(187)
Allowance for Loan Losses, Charge-offs	(8)	(21)	(108)	(245)
Allowance for Loan Losses, Recoveries	10	105	390	156
Allowance for Loan Losses, Ending Allowance	1,109	848	1,109	848
Home Equity Lines Of Credit [Member]
Loans and Leases Receivable Disclosure [Line Items]
Allowance for Loan Losses, Beginning Allowance	51	61	54	60
Allowance for Loan Losses, Provision (benefit)	(4)	(1)	(11)	(4)
Allowance for Loan Losses, Recoveries	2	2	6	6
Allowance for Loan Losses, Ending Allowance	49	62	49	62
Consumer and Overdrafts [Member]
Loans and Leases Receivable Disclosure [Line Items]
Allowance for Loan Losses, Beginning Allowance	10	4	5
Allowance for Loan Losses, Provision (benefit)	6	5
Allowance for Loan Losses, Charge-offs	(16)	(6)
Allowance for Loan Losses, Recoveries	4
Allowance for Loan Losses, Ending Allowance	4	3	4	3
Consumer and Installment Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Allowance for Loan Losses, Beginning Allowance			5	4
Allowance for Loan Losses, Provision (benefit)			28	20
Allowance for Loan Losses, Charge-offs			(34)	(23)
Allowance for Loan Losses, Recoveries			5	2
Allowance for Loan Losses, Ending Allowance	$ 4	$ 3	$ 4	$ 3

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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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 of expense related to estimated loss from loan and lease transactions.

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