LOANS - Summary of activity in the allowance for loan losses by portfolio segment (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Financing Receivable, Past Due [Line Items]
Beginning balance	$ 2,153,174	$ 2,182,174	$ 2,153,174	$ 2,241,174
Provision (credit) for loan losses	100,000	(54,000)	100,000	(113,000)
Ending balance	2,253,174	2,128,174	2,253,174	2,128,174
Commercial Real Estate Portfolio Segment | Residential First Mortgage
Financing Receivable, Past Due [Line Items]
Beginning balance	1,092,474	1,185,674	1,092,474	1,254,174
Provision (credit) for loan losses	159,450	(58,980)	159,450	(127,480)
Ending balance	1,251,924	1,126,694	1,251,924	1,126,694
Commercial Real Estate Portfolio Segment | Commercial and Multi-Family Real Estate
Financing Receivable, Past Due [Line Items]
Beginning balance	768,600	849,000	768,600	841,000
Provision (credit) for loan losses	(88,600)	4,000	(88,600)	12,000
Ending balance	680,000	853,000	680,000	853,000
Commercial Real Estate Portfolio Segment | Construction
Financing Receivable, Past Due [Line Items]
Beginning balance	195,000	48,000	195,000	45,000
Provision (credit) for loan losses	37,000	6,000	37,000	9,000
Ending balance	232,000	54,000	232,000	54,000
Commercial Portfolio Segment
Financing Receivable, Past Due [Line Items]
Beginning balance	9,400	13,500	9,400	14,000
Provision (credit) for loan losses	(2,400)	(5,020)	(2,400)	(5,520)
Ending balance	7,000	8,480	7,000	8,480
Consumer | Home Equity and Other
Financing Receivable, Past Due [Line Items]
Beginning balance	87,700	86,000	87,700	87,000
Provision (credit) for loan losses	5,450		5,450	(1,000)
Ending balance	$ 82,250	$ 86,000	$ 82,250	$ 86,000