DEBT - Interest Expense Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Debt Disclosure [Abstract]
Interest expense	$ 24,243	$ 24,904	$ 72,956	$ 75,900
Non-cash interest expense	1,700	$ 2,100	5,389	$ 6,527
Accrued interest	$ 18,200		$ 18,200		$ 16,100