LOANS - Summary of aging of loans receivable by portfolio segment (Detail) - USD ($)	Sep. 30, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Loans acquired with deteriorated credit quality	$ 4,642,906	$ 5,565,827
Total loans	709,547,582	572,362,843
Commercial and Industrial
Financing Receivable, Past Due [Line Items]
Total loans	1,908,487	7,905,524
Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans acquired with deteriorated credit quality	3,246,758	4,113,571
Total loans	452,252,121	319,968,234
Commercial and Multi-Family Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans acquired with deteriorated credit quality	1,362,947	1,412,995
Total loans	167,043,470	175,375,419
Construction \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans	59,957,043	41,384,687
Home Equity and Other Consumer \| Consumer
Financing Receivable, Past Due [Line Items]
Loans acquired with deteriorated credit quality	33,201	39,261
Total loans	28,386,461	27,728,979
Home Equity and Other Consumer
Financing Receivable, Past Due [Line Items]
Loans acquired with deteriorated credit quality	33,201
Total loans	28,386,461	27,728,979
30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	134,508	27,529
30-59 Days Past Due \| Home Equity and Other Consumer \| Consumer
Financing Receivable, Past Due [Line Items]
Loans Not Past Due		27,529
30-59 Days Past Due \| Home Equity and Other Consumer \| Consumer
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	134,508
60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	575,484	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	556,362	312,616
60-89 Days Past Due \| Home Equity and Other Consumer \| Consumer
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	19,122
Greater than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	282,987	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	282,987	857,676
Past Due
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	992,979	1,197,821
Past Due \| Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	839,349	1,170,292
Past Due \| Home Equity and Other Consumer \| 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	153,630
Not Past Due
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	703,911,697	565,599,195
Not Past Due \| Commercial and Industrial
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	1,908,487	7,905,524
Not Past Due \| Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	448,166,014	314,684,371
Not Past Due \| Commercial and Multi-Family Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	165,680,523	173,962,424
Not Past Due \| Construction \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	59,957,043	41,384,687
Not Past Due \| Home Equity and Other Consumer \| 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	$ 28,199,630

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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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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