EARNINGS PER SHARE - Basic earnings per share of common stock (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Basic and diluted earnings per share:
Net income	$ 594	$ 268
Weighted average common shares outstanding (in shares)	2,843,775	2,829,375
Basic and diluted net income per share of common stock	$ 0.21	$ 0.09
Options outstanding	0	0