REVENUE RECOGNITION - Narrative (Details) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2025 USD ($)	Mar. 31, 2025 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue recognized, included in beginning contract liability	$ 224	$ 646
Backlog	$ 8,800	$ 8,800
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Percentage of backlog recognized as revenue, next 12 months	75.00%	75.00%
Expected timing of satisfaction, backlog	12 months	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected timing of satisfaction, backlog	2 years	2 years