Commitment to lend to customers in addition to outstanding loans classified as troubled debt restructurings.

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Financing receivable modifications number of contracts outstanding.

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Financing receivable modifications recorded investment of specific reserves to customers.

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Loans and leases receivable loan payment deferral granted.

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Number of loans.

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The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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Number of financing receivables that have been modified by troubled debt restructurings.

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Amount of financing receivable modified as troubled debt restructuring.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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Amount, before allowance for credit loss, of financing receivable.

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

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Loans Receivable - Additional Information (Detail)	3 Months Ended		9 Months Ended		12 Months Ended
Loans Receivable - Additional Information (Detail)	Mar. 31, 2022 USD ($) Loan	Mar. 31, 2021 USD ($) Loan	Mar. 31, 2022 USD ($) Loan	Mar. 31, 2021 USD ($) Loan	Jun. 30, 2021 USD ($) Loan
Loans and Leases Receivable Disclosure [Line Items]
Number of loans classified as troubled debt restructurings \| Loan	8		8		12
Value of loans classified as troubled debt restructurings	$ 1,600,000		$ 1,600,000		$ 3,100,000
Troubled debt restructuring with carrying amount			1,200,000		2,700,000
Specific reserves	118,000		118,000		121,000
Commitment to lend to customers in addition to outstanding loans classified as troubled debt restructurings	$ 0		$ 0
Troubled debt restructurings, number of modified loans \| Loan	0	0	0	0
Troubled debt restructurings for which there was a payment default \| Loan	0	0	0	0
Loans receivable	$ 1,294,597,000		$ 1,294,597,000		1,237,332,000
Loans granted	4,490,000		4,490,000		2,681,000
Provision for loan losses	286,000	$ (894,000)	563,000	$ (678,000)
COVID-19 Pandemic [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans granted					27,300,000
COVID-19 Pandemic [Member] \| Pass [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans granted					9,900,000
COVID-19 Pandemic [Member] \| Special Mention [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans granted					3,200,000
COVID-19 Pandemic [Member] \| Substandard [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans granted	3,600,000		3,600,000		14,200,000
Residential Mortgages [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans granted	869,000		869,000		1,272,000
Provision for loan losses	1,000	(4,000)	(21,000)	(49,000)
Commercial Mortgages [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans granted	1,631,000		1,631,000		864,000
Provision for loan losses	206,000	(354,000)	624,000	(395,000)
Commercial Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans granted	423,000		423,000		$ 145,000
Provision for loan losses	40,000	(437,000)	(121,000)	(187,000)
Purchased Credit Impaired Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Provision for loan losses	0	$ 0	$ 0	$ 0
Loan Payment Deferrals [Member] \| COVID-19 Pandemic [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of loans \| Loan			1		19
Loans receivable	0
Loans receivable	3,600,000		$ 3,600,000		$ 27,300,000
Loan Payment Deferrals [Member] \| Residential Mortgages [Member] \| COVID-19 Pandemic [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of loans \| Loan			1
Loans receivable			$ 91,000
Loan Payment Deferrals [Member] \| Commercial Mortgages [Member] \| COVID-19 Pandemic [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of loans \| Loan			2
Loans receivable			$ 5,600,000
Loan Payment Deferrals [Member] \| Commercial Loans [Member] \| COVID-19 Pandemic [Member]
Loans and Leases Receivable Disclosure [Line Items]
Number of loans \| Loan			2
Loans receivable			$ 205,000
90 Days or More Past Due [Member]
Loans and Leases Receivable Disclosure [Line Items]
Acquired loans accounted for as purchased credit impaired loans	351,000		351,000		368,000
Loans granted	4,370,000		4,370,000		1,740,000
90 Days or More Past Due [Member] \| Residential Mortgages [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans granted	869,000		869,000		948,000
90 Days or More Past Due [Member] \| Commercial Mortgages [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans granted	1,631,000		1,631,000		$ 411,000
90 Days or More Past Due [Member] \| Commercial Loans [Member]
Loans and Leases Receivable Disclosure [Line Items]
Loans granted	$ 400,000		$ 400,000