RESTRUCTURING CHARGES - Summary of Accrued Liability for the Restructuring and Related Charges (Details) $ in Thousands	3 Months Ended
	Dec. 31, 2023 USD ($)
Restructuring Reserve [Roll Forward]
Accrued liability beginning balance	$ 19,658
Restructuring charges	12,400
Cash payment	(10,577)
Non-cash charges	(8,482)
Accrued liability ending balance	12,999
Personnel related costs
Restructuring Reserve [Roll Forward]
Accrued liability beginning balance	14,107
Restructuring charges	1,847
Cash payment	(7,215)
Non-cash charges	0
Accrued liability ending balance	8,739
Facilities & Exit Costs
Restructuring Reserve [Roll Forward]
Accrued liability beginning balance	5,551
Restructuring charges	2,071
Cash payment	(3,362)
Non-cash charges	0
Accrued liability ending balance	4,260
Non-cash facility and other
Restructuring Reserve [Roll Forward]
Accrued liability beginning balance	0
Restructuring charges	8,482
Cash payment	0
Non-cash charges	(8,482)
Accrued liability ending balance	$ 0