LOANS - Summary of loans receivable (Detail) - USD ($)	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
Total loans	$ 572,362,843	$ 559,932,027
Allowance for loan losses	(2,153,174)	(2,241,174)	$ (2,016,174)
Net loans	570,209,669	557,690,853
Commercial Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans	7,905,524	13,652,248
Allowance for loan losses	(9,400)	(14,000)	(9,000)
Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans	319,968,234	340,000,989
Allowance for loan losses	(1,092,474)	(1,254,174)	(1,383,174)
Commercial and Multi-Family Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans	175,375,419	171,634,451
Allowance for loan losses	(768,600)	(841,000)	(512,000)
Construction Loans \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans	41,384,687	9,930,959
Allowance for loan losses	(195,000)	(45,000)	(26,000)
Home Equity and Other \| Consumer
Financing Receivable, Past Due [Line Items]
Total loans	27,728,979	24,713,380
Allowance for loan losses	$ (87,700)	$ (87,000)	$ (86,000)

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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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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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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