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LOANS - Summary of allowance for loan losses and the recorded investment in loans by portfolio segments (Detail) - USD ($)	Mar. 31, 2023	Jan. 01, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Individually evaluated for impairment			$ 33,000
Collectively evaluated for impairment			2,545,174
Total ending allowance balance	$ 2,860,949	$ 2,860,949	2,578,174	$ 2,153,174	$ 2,153,174
Loans individually evaluated for impairment			856,659
Loans collectively evaluated for impairment			716,526,580
Loans acquired with deteriorated credit quality			4,220,697
Total ending loan balance	714,751,296	721,729,711	721,603,936
Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Individually evaluated for impairment	10,922,520
Commercial Real Estate Portfolio Segment \| Residential First Mortgage
Financing Receivable, Past Due [Line Items]
Individually evaluated for impairment			33,000
Collectively evaluated for impairment			1,569,534
Total ending allowance balance	1,914,947	1,814,203	1,602,534	1,075,074	1,092,474
Loans individually evaluated for impairment			819,590
Loans collectively evaluated for impairment			462,439,940
Loans acquired with deteriorated credit quality			2,841,097
Total ending loan balance	489,079,665	495,689,840	466,100,627
Commercial Real Estate Portfolio Segment \| Commercial and Multi-Family Real Estate
Financing Receivable, Past Due [Line Items]
Collectively evaluated for impairment			615,480
Total ending allowance balance			615,480	780,000	768,600
Loans collectively evaluated for impairment			160,990,186
Loans acquired with deteriorated credit quality			1,348,483
Total ending loan balance			162,338,669
Commercial Real Estate Portfolio Segment \| Construction
Financing Receivable, Past Due [Line Items]
Individually evaluated for impairment	10,922,520
Collectively evaluated for impairment			258,500
Total ending allowance balance	195,240	260,000	258,500	208,000	195,000
Loans collectively evaluated for impairment			61,825,478
Total ending loan balance	57,379,095	61,825,478	61,825,478
Commercial Portfolio Segment
Financing Receivable, Past Due [Line Items]
Collectively evaluated for impairment			3,960
Total ending allowance balance	4,000	4,000	3,960	9,300	9,400
Loans collectively evaluated for impairment			1,684,189
Total ending loan balance	$ 1,523,380	$ 1,684,189	1,684,189
Consumer \| Home Equity and Other
Financing Receivable, Past Due [Line Items]
Collectively evaluated for impairment			97,700
Total ending allowance balance			97,700	$ 80,800	$ 87,700
Loans individually evaluated for impairment			37,069
Loans collectively evaluated for impairment			29,586,787
Loans acquired with deteriorated credit quality			31,117
Total ending loan balance			$ 29,654,973