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Equity - Narrative (Details) - USD ($) $ in Millions			3 Months Ended		9 Months Ended
Equity - Narrative (Details) - USD ($) $ in Millions	Aug. 05, 2026	Aug. 05, 2025	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Nov. 14, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Non-cash stock-based compensation expense			$ 16	$ 10	$ 43	$ 28
Shared-based compensation liability			1		1
Omnibus Incentive Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share repurchase authorized, amount							$ 100
Forecast \| 10K Projects
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of shares issued in acquisition (in shares)	2,750,000
Subsequent Event \| 10K Projects
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Aggregate consideration		$ 165
Purchase price of selected assets		40
Equity interest		$ 125
Number of shares issued in acquisition (in shares)		1,416,666
Class A Common Stock \| Omnibus Incentive Plan
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Share repurchase authorized, amount							$ 100
Additional Paid-in Capital
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Non-cash stock-based compensation expense					7	$ 15
Shared-based compensation liability			$ 15		$ 42
Common Stock \| Class A Common Stock
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares issued under the plan (in shares)			869,009		2,607,027	1,738,000
Shares issued under omnibus incentive plan (in shares)			5,959	7,000	800,748	185,000