INCOME TAXES - Components of the Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Current:
Federal	$ 15,431	$ 21,745	$ 757
Foreign	1,495	732	6,492
State	523	3,365	2,340
Total current benefit	17,449	25,842	9,589
Deferred:
Federal	(127,096)	(35,809)	(508,256)
Foreign	(12,390)	2,804	7,415
State	(18,069)	(11,549)	14,083
Total deferred benefit	(157,555)	(44,554)	(486,758)
Total benefit	$ (140,106)	$ (18,712)	$ (477,169)