LOANS - Summary of aging of loans receivable by portfolio segment (Detail) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
Loans Past Due	$ 1,409,011	$ 887,507
Loans Not Past Due	576,111,538	559,044,520
Loans acquired with deteriorated credit quality	4,547,261
Total ending loan balance	582,067,810	559,932,027
Commercial and Industrial
Financing Receivable, Past Due [Line Items]
Loans Past Due	992,354
Loans Not Past Due	9,159,506	13,652,248
Loans acquired with deteriorated credit quality	0
Total ending loan balance	10,151,860	13,652,248
Consumer
Financing Receivable, Past Due [Line Items]
Loans Past Due	21,692
Loans Not Past Due	28,315,800
Loans acquired with deteriorated credit quality	19,302
Total ending loan balance	28,356,794	24,713,380
Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Past Due	394,965	727,125
Loans Not Past Due	324,912,185	339,273,864
Loans acquired with deteriorated credit quality	3,570,975
Total ending loan balance	328,878,125	340,000,989
Commercial and Multi-Family Real Estate \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Past Due	0
Loans Not Past Due	176,573,114	171,634,451
Loans acquired with deteriorated credit quality	956,984
Total ending loan balance	177,530,098	171,634,451
Construction \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Not Past Due	37,150,933	9,930,959
Total ending loan balance	37,150,933	9,930,959
Home Equity Loan \| Consumer
Financing Receivable, Past Due [Line Items]
Loans Past Due		160,382
Loans Not Past Due		24,552,998
Total ending loan balance	28,356,794	24,713,380
30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans Past Due	0	160,382
30-59 Days Past Due \| Consumer
Financing Receivable, Past Due [Line Items]
Loans Past Due	0
30-59 Days Past Due \| Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Past Due	0
30-59 Days Past Due \| Home Equity Loan \| Consumer
Financing Receivable, Past Due [Line Items]
Loans Past Due		160,382
60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans Past Due	1,296,004	702,497
60-89 Days Past Due \| Commercial and Industrial
Financing Receivable, Past Due [Line Items]
Loans Past Due	992,354
60-89 Days Past Due \| Consumer
Financing Receivable, Past Due [Line Items]
Loans Past Due	21,692
60-89 Days Past Due \| Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Past Due	281,958	702,497
Greater than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans Past Due	113,007	24,628
Greater than 89 Days Past Due \| Consumer
Financing Receivable, Past Due [Line Items]
Loans Past Due	0
Greater than 89 Days Past Due \| Residential First Mortgage \| Commercial Real Estate Portfolio Segment
Financing Receivable, Past Due [Line Items]
Loans Past Due	$ 113,007	$ 24,628

Fair value at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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