Loans - Risk category of loans (Details) - USD ($)	Sep. 30, 2022	Jun. 30, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	$ 195,543,646	$ 187,900,474
Commercial real estate [Member] | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	84,854,449	80,603,153
Commercial [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	101,751,199	99,964,364
Commercial [Member] | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	84,854,449	80,603,153
Commercial [Member] | Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	9,209,475	8,778,723
Commercial [Member] | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	7,687,275	10,582,488
Commercial [Member] | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	100,348,945	98,575,589
Commercial [Member] | Pass | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	83,452,195	79,214,378
Commercial [Member] | Pass | Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	9,209,475	8,778,723
Commercial [Member] | Pass | Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	7,687,275	10,582,488
Commercial [Member] | Special Mention/Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,378,705	1,388,775
Commercial [Member] | Special Mention/Watch | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	1,378,705	1,388,775
Commercial [Member] | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	23,549
Commercial [Member] | Substandard | Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	23,549
Consumer Loans [Member] | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	$ 2,137,459	$ 2,100,259