Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Accounting Policies [Line Items]
Total assets	$ 9,155	$ 8,545
Total liabilities	8,480	8,115
Foreign currency transaction gain (loss) recognized	2	4	$ (11)
Foreign currency transaction gain (loss) recognized in other income (expense)	(72)	(37)	185
Advertising expense	$ 119	$ 136	$ 155
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%	18.00%
Variable Interest Entity, Primary Beneficiary
Accounting Policies [Line Items]
Total assets	$ 77	$ 5
Total liabilities	$ 2	$ 2