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Loans - Risk category of loans (Details) - USD ($)	6 Months Ended
Loans - Risk category of loans (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2023
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			$ 199,935,846
Net change in other assets	$ (190,193)	$ 2,961
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			93,364,410
Commercial \| Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			84,580,946
Commercial \| Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			6,878,209
Commercial \| Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			1,905,255
Commercial \| Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			93,364,410
Commercial \| Pass \| Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			84,580,946
Commercial \| Pass \| Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			6,878,209
Commercial \| Pass \| Construction
Financing Receivable, Credit Quality Indicator [Line Items]
Total loans			$ 1,905,255