Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount, after tax, of realized gain (loss) from foreign currency transaction.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount, after tax, of unrealized gain (loss) from foreign currency transaction.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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No definition available.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Accounting policies.

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Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Accounting Policies [Line Items]
Foreign currency transaction gain (loss) recognized	$ 4	$ (11)	$ 0
Foreign currency transaction gain (loss) recognized in other income (expense)	(37)	185	(8)
Advertising expense	$ 136	$ 155	$ 149
Award requisite service period	4 years
Performance Share Units PSU
Accounting Policies [Line Items]
Award requisite service period	3 years
Furniture and fixtures \| Minimum
Accounting Policies [Line Items]
Property plant and equipment useful life	5 years
Furniture and fixtures \| Maximum
Accounting Policies [Line Items]
Property plant and equipment useful life	7 years
Computer Equipment \| Maximum
Accounting Policies [Line Items]
Property plant and equipment useful life	5 years
Machinery and equipment \| Maximum
Accounting Policies [Line Items]
Property plant and equipment useful life	13 years
Building \| Maximum
Accounting Policies [Line Items]
Property plant and equipment useful life	40 years
Spotify \| Accounts Receivable \| Credit Concentration Risk
Accounting Policies [Line Items]
Customer concentration percentage (as a percent)	18.00%	17.00%