LOANS - Summary of activity in the allowance for credit losses by portfolio segment (Detail) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Financing Receivable, Past Due [Line Items]
Beginning balance	$ 2,860,949	$ 2,153,174	$ 2,578,174	$ 2,153,174
Impact of ASC 326 adoption			282,775
Provision for loan losses (credit)	(125,000)	100,000	(125,000)	100,000
Provision for (recovery) of credit losses	(75,000)	100,000	(75,000)	100,000
Ending balance	2,785,949	2,253,174	2,785,949	2,253,174
Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Beginning balance			3,960
Commercial Real Estate Portfolio Segment \| Residential First Mortgage
Financing Receivable, Past Due [Line Items]
Beginning balance	1,914,947	1,092,474	1,602,534	1,092,474
Impact of ASC 326 adoption			113,969
Provision for (recovery) of credit losses	(103,400)	159,450	95,044	159,450
Ending balance	1,811,547	1,251,924	1,811,547	1,251,924
Commercial Real Estate Portfolio Segment \| Commercial Real Estate
Financing Receivable, Past Due [Line Items]
Beginning balance	423,002		381,180
Impact of ASC 326 adoption			141,797
Provision for (recovery) of credit losses	116,000		16,025
Ending balance	539,002		539,002
Commercial Real Estate Portfolio Segment \| Multi-Family Real Estate
Financing Receivable, Past Due [Line Items]
Beginning balance	278,000		234,300
Impact of ASC 326 adoption			25,469
Provision for (recovery) of credit losses	(13,000)		5,231
Ending balance	265,000		265,000
Commercial Real Estate Portfolio Segment \| Commercial and Multi-Family Real Estate
Financing Receivable, Past Due [Line Items]
Beginning balance		768,600	615,480	768,600
Provision for (recovery) of credit losses		(88,600)		(88,600)
Ending balance	539,002	680,000	539,002	680,000
Commercial Real Estate Portfolio Segment \| Construction
Financing Receivable, Past Due [Line Items]
Beginning balance	241,000	195,000	258,500	195,000
Impact of ASC 326 adoption			1,500
Provision for (recovery) of credit losses	(82,000)	37,000	(101,000)	37,000
Ending balance	159,000	232,000	159,000	232,000
Commercial Real Estate Portfolio Segment \| Home Equity and Other
Financing Receivable, Past Due [Line Items]
Beginning balance			97,700
Provision for (recovery) of credit losses			(97,700)
Commercial Portfolio Segment
Financing Receivable, Past Due [Line Items]
Beginning balance	4,000	9,400	3,960	9,400
Impact of ASC 326 adoption			40
Provision for (recovery) of credit losses	7,400	(2,400)	7,400	(2,400)
Ending balance	11,400	7,000	11,400	7,000
Commercial Portfolio Segment \| Construction
Financing Receivable, Past Due [Line Items]
Ending balance	159,000		159,000
Consumer
Financing Receivable, Past Due [Line Items]
Ending balance	$ 11,400		11,400
Consumer \| Home Equity and Other
Financing Receivable, Past Due [Line Items]
Beginning balance		87,700	$ 97,700	87,700
Provision for (recovery) of credit losses		(5,450)		(5,450)
Ending balance		$ 82,250		$ 82,250

Impact of current expected credit losses adjustment

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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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 of expense related to estimated loss from loan and lease transactions.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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