INCOME TAXES - Components And Provisions (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Components income/ (loss) before income taxes
United States									$ (173,506)	$ (279,822)	$ (71,171)
Foreign									19,396	15,291	11,281
Income/ (loss) before income taxes									(154,110)	(264,531)	(59,890)
Provision for federal, state, and foreign income taxes
Federal - Current									1,308	(722)
Federal - Deferred									(1,998)	(59,425)	(8,961)
State - Current									311	1,405	830
State - Deferred									2,330	(7,176)	(2,740)
Foreign - Current									3,435	5,794	3,112
Foreign - Deferred									3,021	(122)	(4,028)
Income tax expense (benefit)	$ 3,496	$ (733)	$ 1,619	$ 4,025	$ (27,322)	$ (37,002)	$ 2,074	$ 2,004	$ 8,407	$ (60,246)	$ (11,787)