REVENUE AND RECEIVABLES - Allowance for Credit Losses Rollforward - (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
REVENUE AND RECEIVABLES
Beginning Balance	$ 12,121	$ 12,724
Current period provision for expected losses	4,850	5,010	$ 5,816
Write-offs charged against the allowance	(3,517)	(6,351)
Recoveries collected	431	738
Ending Balance	$ 13,885	$ 12,121	$ 12,724