Loans - Additional information (Details)	12 Months Ended
Jun. 30, 2020 USD ($) loan	Jun. 30, 2019 USD ($) loan
Loans
Aggregate Amount of Purchased Participants	$ 5,600,000	$ 9,100,000
Aggregate Amount of Purchased Participants, Portion	$ 9,000,000	$ 6,900,000
Number of loans past due 90 days or over that were not on nonaccrual \| loan	0	0
Loans outstanding to certain directors and executive officers of the Bank	$ 1,080,531	$ 1,039,899
Number of new related party loans \| loan	1	0
Related party loan addition	$ 90,400
Repayments of related party loans	$ 49,768	$ 40,226
TDR's granted during the period \| loan	1	0
TDR's outstanding	$ 195,924
TDR's defaulted during the period \| loan	0

The aggregate amount of purchased participants.

No definition available.

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Period Type:	duration

- Definition

The aggregate amount of our portion of purchased participants.

+ References

No definition available.

+ Details

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- Definition

Number of loans past due 90 days or over that were not on nonaccrual.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Number of related party loan entered into during the period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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- Definition

Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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Balance Type:	debit
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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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- Definition

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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(e))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

+ References

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- References

No definition available.

+ Details

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- Definition

The cash inflow from a loan, supported by a promissory note, granted to related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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