LOANS - Summary of aging of loans receivable by portfolio segment (Detail) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Loans acquired with deteriorated credit quality	$ 5,142,148	$ 5,565,827
Total loans	566,580,015	572,362,843
Commercial and Industrial
Financing Receivable, Past Due [Line Items]
Total loans	3,494,447	7,905,524
Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans acquired with deteriorated credit quality	3,708,833	4,113,571
Total loans	316,657,570	319,968,234
Commercial and Multi-Family \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans acquired with deteriorated credit quality	1,396,055	1,412,995
Total loans	177,225,830	175,375,419
Construction \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans	43,639,387	41,384,687
Home Equity Loan \| Consumer
Financing Receivable, Past Due [Line Items]
Loans acquired with deteriorated credit quality	37,260	39,261
Total loans	25,562,781	27,728,979
Home Equity and Other Consumer
Financing Receivable, Past Due [Line Items]
Loans acquired with deteriorated credit quality	37,260
Total loans	25,562,781	27,728,979
30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	368,542	27,529
30-59 Days Past Due \| Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	368,542
30-59 Days Past Due \| Home Equity Loan \| Consumer
Financing Receivable, Past Due [Line Items]
Loans Not Past Due		27,529
60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	238,762	312,616
60-89 Days Past Due \| Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	217,737	312,616
60-89 Days Past Due \| Home Equity and Other Consumer
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	21,025
Greater than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	151,621	857,676
Greater than 89 Days Past Due \| Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	151,621	857,676
Past Due
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	758,925	1,197,821
Past Due \| Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	737,900	1,170,292
Past Due \| Home Equity Loan \| Consumer
Financing Receivable, Past Due [Line Items]
Loans Not Past Due		27,529
Past Due \| Home Equity and Other Consumer
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	21,025
Not Past Due
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	560,678,942	565,599,195
Not Past Due \| Commercial and Industrial
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	3,494,447	7,905,524
Not Past Due \| Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	312,210,837	314,684,371
Not Past Due \| Commercial and Multi-Family \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	175,829,775	173,962,424
Not Past Due \| Construction \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	43,639,387	41,384,687
Not Past Due \| Home Equity Loan \| Consumer
Financing Receivable, Past Due [Line Items]
Loans Not Past Due		$ 27,662,189
Not Past Due \| Home Equity and Other Consumer
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	$ 25,504,496

Fair value at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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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.

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