Segment Information - Schedule of Components of Adjusted OIBDA to Operating Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024
Segment Reporting [Abstract]
Operating income	$ 168	$ 119	$ 382	$ 473
Amortization expense	62	57	119	112
Depreciation expense	28	26	57	52
Restructuring and impairments	13	95	40	95
Transformation initiative costs	18	19	35	38
Net gain on divestitures	0	(14)	0	(31)
Non-cash stock-based compensation and other related costs	14	10	33	24
Adjusted OIBDA	$ 303	$ 312	$ 666	$ 763

Amount of expense for allocation of cost of intangible asset over its useful life directly used in production of good and rendering of service.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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The net result for the period of deducting operating expenses from operating revenues.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

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Income loss from continuing operations before income taxes depreciation and amortization.

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Non-Cash Stock-Based Compensation and Other Related Costs

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Transformation Initiatives And Other Related Costs

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