Loan Quality and Allowance for Loan Losses - Additional Information (Detail)	Dec. 31, 2018 USD ($) Property Loan	Jun. 30, 2018 USD ($) Property Loan
Financing Receivable Recorded Investment [Line Items]
Other real estate owned	$ 508,000	$ 725,000
Residential Mortgage [Member]
Financing Receivable Recorded Investment [Line Items]
Number of loans in process of foreclosure \| Loan	17	14
Mortgage loans in process of foreclosure, carrying value	$ 3,200,000	$ 2,300,000
Residential Mortgage [Member] \| Single-family Property [Member]
Financing Receivable Recorded Investment [Line Items]
Other real estate owned	$ 508,000	$ 725,000
Residential Mortgage [Member] \| Real Estate Acquired in Satisfaction of Debt [Member] \| Single-family Property [Member]
Financing Receivable Recorded Investment [Line Items]
Number of properties held \| Property	2	4

Mortgage loans in process of foreclosure, number of loans.

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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.

+ Details

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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL49126937-111524

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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