REVENUE RECOGNITION - Schedule of Changes in Contract Asset and Liability Balances (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Contract liabilities
Contract liabilities, beginning	$ 1,783	$ 1,731
Recognition of revenue included in beginning of year contract liabilities	(1,475)	(1,720)
Contract liabilities, net of revenue recognized on contracts during the period	6,688	1,772
Reversal of contract liabilities due to changes in transaction price	(200)	0
Contract liabilities, ending	$ 6,796	$ 1,783