SECURITIES HELD TO MATURITY - Summary of amortized cost, fair value, and gross unrecognized gains and losses of securities held to maturity (Detail) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Marketable Securities [Line Items]
Amortized Cost	$ 60,442,805	$ 57,504,443
Gross Unrealized Gains	1,208,495	1,445,151
Gross Unrealized Losses	(648,406)	(77,143)
Fair Value	61,002,894	58,872,451
U.S. Government-sponsored Agencies
Marketable Securities [Line Items]
Securities held to maturity, due in more than ten years, Amortized Cost	2,000,439
Securities held to maturity, due in more than ten years, Gross Unrealized Losses	(439)
Securities held to maturity, due in more than ten years, Fair Value	2,000,000
Corporate Bonds
Marketable Securities [Line Items]
Securities held to maturity, due in Less than one year, Amortized Cost		1,501,179
Securities held to maturity, due in One through five years, Amortized Cost		8,635,831
Securities held to maturity, due in Five through ten years, Amortized Cost	12,672,024
Securities held to maturity, due in Less than one year, Gross Unrealized Gains		13,616
Securities held to maturity, due in One through five years, Gross Unrealized Gains		221,716
Securities held to maturity, due in Five through ten years, Gross Unrealized Gains	408,034
Securities held to maturity, due in One through five years, Gross Unrealized Losses		(2,520)
Securities held to maturity, due in Five through ten years, Gross Unrealized Losses	(64,463)
Securities held to maturity, due in Less than one year, Fair Value		1,514,795
Securities held to maturity, due in One through five years, Fair Value		8,855,027
Securities held to maturity, due in Five through ten years, Fair Value	13,015,595
Municipal Obligations
Marketable Securities [Line Items]
Securities held to maturity, due in Less than one year, Amortized Cost		2,764,079
Securities held to maturity, due in One through five years, Amortized Cost	3,818,767	1,057,609
Securities held to maturity, due in Five through ten years, Amortized Cost	375,000	375,000
Securities held to maturity, due in Less than one year, Gross Unrealized Gains		4,944
Securities held to maturity, due in One through five years, Gross Unrealized Gains	29,391	30,492
Securities held to maturity, due in Five through ten years, Gross Unrealized Gains	25,043	32,201
Securities held to maturity, due in Less than one year, Gross Unrealized Losses		(141)
Securities held to maturity, due in Less than one year, Fair Value		2,768,882
Securities held to maturity, due in One through five years, Fair Value	3,848,158	1,088,101
Securities held to maturity, due in Five through ten years, Fair Value	400,043	407,201
Residential Mortgage Backed Securities
Marketable Securities [Line Items]
Amortized Cost	17,822,528	11,906,884
Gross Unrealized Gains	117,631	144,863
Gross Unrealized Losses	(371,643)	(15,440)
Fair Value	17,568,516	12,036,307
Commercial Mortgage Backed Securities
Marketable Securities [Line Items]
Amortized Cost	23,754,047	31,263,861
Gross Unrealized Gains	628,396	997,319
Gross Unrealized Losses	(211,861)	(59,042)
Fair Value	$ 24,170,582	$ 32,202,138

Debt securities held to maturity maturities after ten years accumulated unrecognized loss.

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