REVENUE - TIMING OF REVENUE RECOGNITION (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Timing of Revenue Recognition [Roll Forward]
Customers' credit, beginning	$ 31,297	$ 38,595
Increase for customers' credits	8,948	3,992
Customers' credit, end	40,245	42,587
Billed
Timing of Revenue Recognition [Roll Forward]
Billed, beginning	109,366	105,531
Increase for customer accounts receivable	150,763	105,505
Billed, end	260,129	211,036
Unbilled
Timing of Revenue Recognition [Roll Forward]
Billed, beginning	24,194	20,094
Increase for customer accounts receivable	127,759	97,186
Billed, end	$ 151,953	$ 117,280