EARNINGS PER SHARE - Basic earnings per share of common stock (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Basic earnings per share:
Net income	$ 551,441	$ 375,009	$ 1,261,822	$ 915,274
Weighted average common shares outstanding, basic	2,875,329	2,860,352	2,869,631	2,857,759
Net income per share (basic)	$ 0.19	$ 0.13	$ 0.44	$ 0.32
Net income per share (diluted)	$ 0.19	$ 0.13	$ 0.44	$ 0.32
Options outstanding	0	0	0	0