WARRANTY LIABILITY - Changes in Warrant Liability (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Balance, beginning of period	$ 20,781	$ 16,786
Warranties issued and changes in estimated pre-existing warranties	940	4,667
Actual warranty costs incurred	(6,260)	(3,754)
Balance, end of period	$ 15,461	$ 17,699