Segment Information - Schedule of Segment Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Segment Reporting Information [Line Items]
Revenue	$ 1,689	$ 1,554	$ 4,839	$ 4,796
Adjusted OIBDA	373	316	1,039	1,079
Operating Segments \| Recorded Music
Segment Reporting Information [Line Items]
Revenue	1,354	1,251	3,874	3,885
Adjusted OIBDA	321	281	914	965
Operating Segments \| Music Publishing
Segment Reporting Information [Line Items]
Revenue	336	305	969	915
Adjusted OIBDA	96	79	264	247
Corporate expenses and eliminations
Segment Reporting Information [Line Items]
Revenue	(1)	(2)	(4)	(4)
Adjusted OIBDA	$ (44)	$ (44)	$ (139)	$ (133)

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

Warner Music Group Corp. 10-Q