LONG-TERM DEBT - Net Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Debt Disclosure [Abstract]
Interest expense	$ 21,505	$ 25,253	$ 45,059	$ 50,987
Amortization of deferred financing costs	998	671	1,943	1,472
Amortization of original issue discount (premium) of senior notes	(849)	(855)	(1,698)	(1,570)
Interest income and other investment income	(12)	(125)	(41)	(725)
Total net interest expense	$ 21,642	$ 24,944	$ 45,263	$ 50,164