Loans Receivable - Summary of Loans Individually Evaluated for Impairment (Excluding Loans Acquired with Deteriorated Credit Quality) by Portfolio Segment (Detail) - USD ($) $ in Thousands	Mar. 31, 2022	Jun. 30, 2021
Financing Receivable Impaired [Line Items]
Allowance for loan losses	$ 118	$ 121
Impaired loans, unpaid principal balance	8,644	8,258
Impaired loans, recorded investment	8,670	8,059
Residential Mortgages [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, unpaid principal balance	1,365	2,044
Impaired loans with no related allowance recorded, recorded investment	1,323	1,931
Impaired loans with an allowance recorded, unpaid principal balance	356	363
Impaired loans with an allowance recorded, recorded investment	417	425
Allowance for loan losses	110	113
Impaired loans, recorded investment	1,740	2,356
Commercial Mortgages [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, unpaid principal balance	4,796	3,582
Impaired loans with no related allowance recorded, recorded investment	4,790	3,582
Impaired loans, recorded investment	4,790	3,582
Construction [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, unpaid principal balance	1,113
Impaired loans with no related allowance recorded, recorded investment	1,113
Impaired loans, recorded investment	1,113
Commercial Loans [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, unpaid principal balance	664	1,878
Impaired loans with no related allowance recorded, recorded investment	652	1,707
Impaired loans, recorded investment	652	1,707
Home Equity Lines Of Credit [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, unpaid principal balance	314	358
Impaired loans with no related allowance recorded, recorded investment	339	381
Impaired loans with an allowance recorded, unpaid principal balance	36	33
Impaired loans with an allowance recorded, recorded investment	36	33
Allowance for loan losses	8	8
Impaired loans, recorded investment	$ 375	$ 414

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
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