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, 2020	Jun. 30, 2019
Financing Receivable Impaired [Line Items]
Impaired loans, unpaid principal balance	$ 5,035	$ 6,203
Impaired loans, recorded investment	4,767	5,897
Allowance for loan losses	123	173
Residential [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, unpaid principal balance	2,131	1,061
Impaired loans with no related allowance recorded, recorded investment	2,024	1,028
Impaired loans with an allowance recorded, unpaid principal balance	373	723
Impaired loans with an allowance recorded, recorded investment	434	746
Impaired loans, recorded investment	2,458	1,774
Allowance for loan losses	118	130
Commercial Loans [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, unpaid principal balance	2,105	2,007
Impaired loans with no related allowance recorded, recorded investment	1,934	1,836
Impaired loans with an allowance recorded, unpaid principal balance	26	180
Impaired loans with an allowance recorded, recorded investment	26	180
Impaired loans, recorded investment	1,960	2,016
Allowance for loan losses	1	39
Home Equity Lines Of Credit [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, unpaid principal balance	389	750
Impaired loans with no related allowance recorded, recorded investment	338	678
Impaired loans with an allowance recorded, unpaid principal balance	11	11
Impaired loans with an allowance recorded, recorded investment	11	11
Impaired loans, recorded investment	349	689
Allowance for loan losses	$ 4	4
Commercial [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, unpaid principal balance		1,471
Impaired loans with no related allowance recorded, recorded investment		1,418
Impaired loans, recorded investment		$ 1,418

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)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

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The balance of financing receivables that were individually evaluated for impairment.

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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