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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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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Summary of Effect of Adoption of ASC 326 on Loan Portfolio Segments and ACL by Portfolio Segment (Detail) - USD ($)	Jun. 30, 2023	Mar. 31, 2023	Jan. 01, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Total loans	$ 708,732,034		$ 721,729,711	$ 721,603,936
Allowance for credit losses	(2,785,949)	$ (2,860,949)	(2,860,949)	(2,578,174)	$ (2,253,174)	$ (2,153,174)	$ (2,153,174)
Net loans	705,946,085		718,868,762	719,025,762
Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Allowance for credit losses				(3,960)
Commercial Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans	3,692,425		1,684,189	1,684,189
Allowance for credit losses	(11,400)	(4,000)	4,000	(3,960)	(7,000)	(9,400)	(9,400)
Consumer
Financing Receivable, Past Due [Line Items]
Allowance for credit losses	(11,400)
Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans	488,571,980		495,689,840	466,100,627
Allowance for credit losses	(1,811,547)	(1,914,947)	(1,814,203)	(1,602,534)	(1,251,924)	(1,092,474)	(1,092,474)
Commercial and Multi-Family Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans				162,338,669
Allowance for credit losses	(539,002)			(615,480)	(680,000)	(768,600)	(768,600)
Commercial Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans	100,761,175		96,030,721
Allowance for credit losses	(539,002)	(423,002)	(522,977)	(381,180)
Multi-Family Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans	67,007,772		66,400,713
Allowance for credit losses	(265,000)	(278,000)	(259,769)	(234,300)
Construction \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans	48,678,332		61,825,478	61,825,478
Allowance for credit losses	(159,000)	$ (241,000)	(260,000)	(258,500)	(232,000)	(195,000)	(195,000)
Construction \| Commercial Portfolio Segment
Financing Receivable, Past Due [Line Items]
Allowance for credit losses	(159,000)
Home Equity and Other Consumer \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Allowance for credit losses				(97,700)
Home Equity and Other Consumer \| Consumer
Financing Receivable, Past Due [Line Items]
Total loans				29,654,973
Allowance for credit losses				(97,700)	$ (82,250)	$ (87,700)	$ (87,700)
Consumer \| Consumer
Financing Receivable, Past Due [Line Items]
Total loans	$ 20,350		98,770
Pre Adoption
Financing Receivable, Past Due [Line Items]
Total loans			721,603,936	721,729,711
Allowance for credit losses			(2,578,174)	(2,860,949)
Net loans			719,025,762	718,868,762
Pre Adoption \| Commercial Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans			1,684,189	1,684,189
Allowance for credit losses			(3,960)
Pre Adoption \| Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans			466,100,627	495,689,840
Allowance for credit losses			(1,602,534)
Pre Adoption \| Commercial and Multi-Family Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans			162,338,669
Allowance for credit losses			(615,480)
Pre Adoption \| Commercial Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans				96,030,721
Pre Adoption \| Multi-Family Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans				66,400,713
Pre Adoption \| Construction \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans			61,825,478	61,825,478
Allowance for credit losses			(258,500)
Pre Adoption \| Home Equity and Other Consumer \| Consumer
Financing Receivable, Past Due [Line Items]
Total loans			29,654,973
Allowance for credit losses			(97,700)
Pre Adoption \| Consumer \| Consumer
Financing Receivable, Past Due [Line Items]
Total loans				98,770
The Effect of Adoption
Financing Receivable, Past Due [Line Items]
Total loans			125,775	125,775
Allowance for credit losses			(282,775)	(282,775)
Net loans			(157,000)	(157,000)
The Effect of Adoption \| Commercial Portfolio Segment
Financing Receivable, Past Due [Line Items]
Allowance for credit losses			(40)
The Effect of Adoption \| Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans			29,589,213	29,589,213
Allowance for credit losses			(211,669)
The Effect of Adoption \| Commercial and Multi-Family Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans			(162,338,669)	(162,338,669)
Allowance for credit losses			615,480
The Effect of Adoption \| Commercial Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans			96,030,721	96,030,721
Allowance for credit losses			(522,977)
The Effect of Adoption \| Multi-Family Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Total loans			66,400,713	66,400,713
Allowance for credit losses			(259,769)
The Effect of Adoption \| Construction \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Allowance for credit losses			(1,500)
The Effect of Adoption \| Home Equity and Other Consumer \| Consumer
Financing Receivable, Past Due [Line Items]
Total loans			(29,654,973)	(29,654,973)
Allowance for credit losses			97,700
The Effect of Adoption \| Consumer \| Consumer
Financing Receivable, Past Due [Line Items]
Total loans			$ 98,770	$ 98,770