Loans - Risk category of loans (Details) - USD ($)	12 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	$ 187,900,474	$ 146,873,595
Commercial real estate [Member] \| Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	80,603,153	52,148,065
Commercial real estate [Member] \| Commercial real estate \| Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	79,214,378	51,924,082
Loans risk rating reclassified	3,400,000
Commercial real estate [Member] \| Commercial real estate \| Special Mention/Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,388,775	223,983
Proceeds from loans	242,000
Commercial [Member] \| Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	8,778,723	19,278,477
Commercial [Member] \| Commercial and industrial \| Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	8,778,723	14,245,538
Loans risk rating reclassified	1,600,000
Commercial [Member] \| Commercial and industrial \| Special Mention/Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans		5,032,939
Commercial [Member] \| Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	10,582,488	7,985,188
Commercial [Member] \| Construction \| Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	10,582,488	7,985,188
Commercial Real Estate And Commercial Portfolio
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	99,964,364	79,411,730
Commercial Real Estate And Commercial Portfolio \| Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	98,575,589	74,154,808
Commercial Real Estate And Commercial Portfolio \| Special Mention/Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	$ 1,388,775	$ 5,256,922

Amount before allowance of loans and leases held in portfolio, risk rating reclassified.

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+ References

No definition available.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522

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Cash inflow related to a loan origination (the process when securing a mortgage for a piece of real property), lease origination, and principal collections.

+ 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
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3179-108585

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