Loans Receivable - Schedule of Carrying Amount of Purchased Credit Impaired Loans (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Jun. 30, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount of loans	$ 1,229,451	$ 1,260,947
Residential Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount of loans	720	739
Commercial Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount of loans	888	882
Acquired with Deteriorated Credit Quality [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount of loans	1,731	1,760
Acquired with Deteriorated Credit Quality [Member] \| Home Equity Lines Of Credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount of loans	$ 123	$ 139

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Name:	us-gaap_LoansAndLeasesReceivableNetReportedAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant