INCOME TAXES - Income tax (benefit) expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Current:
Federal	$ 7,970	$ 3,076
State and local	1,859	323
Total current tax expense	9,829	3,399
Deferred:
Federal	(1,392)	(1,338)
State and local	(280)	122
Valuation allowance	372
Total deferred (benefit) tax	(1,300)	(1,216)
Income tax expense	$ 8,529	$ 2,183
Effective income tax rate (as a percent)	21.00%	21.00%