Segment Information - Schedule of Components of Adjusted OIBDA to Operating Income (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting [Abstract]
Operating income	$ 354	$ 265	$ 790	$ 714	$ 609
Amortization expense	55	63	245	263	229
Depreciation expense	26	21	87	76	77
Restructuring	19	12	42	8	18
Transformation initiatives and other related costs			53	46	36
Executive transition costs			7	0	0
Net loss (gain) on divestitures	(17)	(41)	(41)	0	0
COVID-19 related costs			0	0	1
Non-cash stock-based compensation and other related costs	14	15	52	42	48
Adjusted OIBDA	$ 451	$ 335	$ 1,235	$ 1,149	$ 1,018

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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Discloses the amount charged against the accrued restructuring reserves, or earnings if not previously accrued, during the period for the specified type of restructuring cost.

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

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Transformation initiatives and other related costs

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