Loans Receivable - Summary of Average Recorded Investment and Interest Income Recognized on Loans Individually Evaluated for Impairment, by Portfolio Segment (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Financing Receivable Impaired [Line Items]
Impaired loans average recorded investment	$ 5,364	$ 6,079	$ 6,075	$ 7,779
Impaired loans interest income recognized	78	66	375	216
Residential [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, average recorded investment	2,060	1,317	2,050	1,516
Impaired loans with no related allowance recorded, interest income recognized	13	9	40	20
Impaired loans with an allowance recorded, average recorded investment	435	750	437	752
Impaired loans with an allowance recorded, interest income recognized	4		11
Impaired loans with an allowance recorded, interest income recognized		4		11
Commercial [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, average recorded investment	485	1,408	946	1,494
Impaired loans with no related allowance recorded, interest income recognized	9	11	149	37
Construction [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, average recorded investment				2,131
Impaired loans with no related allowance recorded, interest income recognized				138
Impaired loans with an allowance recorded, average recorded investment				1,130
Commercial Loans [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, average recorded investment	1,932	1,862	2,015	628
Impaired loans with no related allowance recorded, interest income recognized	51	42	154	9
Impaired loans with an allowance recorded, average recorded investment	38	39	42	40
Impaired loans with an allowance recorded, interest income recognized			1
Impaired loans with an allowance recorded, interest income recognized				1
Home Equity Lines Of Credit [Member]
Financing Receivable Impaired [Line Items]
Impaired loans with no related allowance recorded, average recorded investment	403	616	574
Impaired loans with no related allowance recorded, interest income recognized	7		20
Impaired loans with an allowance recorded, average recorded investment	11	$ 87	$ 11	$ 88
Impaired loans with an allowance recorded, interest income recognized	$ (6)

Impaired financing receivable with no related allowance interest income (expense) accrual method.

No definition available.

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- Definition

Impaired financing receivable with related allowance interest income earned and reversal of accrual method.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5258-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

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- Definition

Amount of average investment of impaired financing receivables for which there is a related allowance for credit losses.

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- Definition

Amount of interest income, recognized on accrual basis, on financing receivables, for which there is a related allowance for credit losses and are recognized as impaired.

+ References

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