Loans - loans by class based on payment activity (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
Residential [Member] | One-to-four-family residential
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	56,367,980	51,890,948
Residential [Member] | One-to-four-family residential | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	56,362,218	51,827,163
Residential [Member] | One-to-four-family residential | Non-performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	5,762	63,785
Residential [Member] | Multi-family real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	35,287,008	33,944,903
Residential [Member] | Multi-family real estate | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	35,287,008	33,944,903
Residential Real Estate And Consumer Portfolio
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	93,792,447	87,936,110
Residential Real Estate And Consumer Portfolio | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	93,786,685	87,872,325
Residential Real Estate And Consumer Portfolio | Non-performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	5,762	63,785
Consumer Loans [Member] | Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	2,137,459	2,100,259
Consumer Loans [Member] | Consumer | Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans	$ 2,137,459	$ 2,100,259