Regulatory Capital Requirements - Additional Information (Details) - USD ($)	9 Months Ended
Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019
Regulatory Capital Requirements
Percentage of capital conversion buffer	2.50%
Percentage of bank's net worth of total assets	6.00%
Bank's net worth of total assets	$ 24,716,999	$ 23,501,513
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	$ 1,102,641	$ 1,190,650	$ 1,180,550
Percentage of net worth on assets	8.70%	7.90%

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- Definition

Information about minimum net worth required for compliance.

+ References

No definition available.

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Information about net worth required for compliance.

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- Definition

Percentage of capital conversion buffer.

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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- Definition

The lowest amount of net worth (total assets minus total liabilities) required by secondary market investors or state-imposed regulatory mandates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47304-110998

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)(a)
-URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47080-110998

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