Consolidated Statements of Equity - USD ($) $ in Millions	Total	Class A Common Stock	Class B Common Stock	Total Warner Music Group Corp. Equity (Deficit)	Common Stock Class A Common Stock	Common Stock Class B Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss	Non-controlling Interest
Beginning balance (in shares) at Sep. 30, 2021					122,414,000	391,971,000
Beginning balance at Sep. 30, 2021	$ 46			$ 31	$ 0	$ 1	$ 1,942	$ (1,710)	$ (202)	$ 15
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	555			551				551		4
Other comprehensive (loss) income, net of tax	(145)			(145)					(145)
Dividends	(318)			(318)				(318)
Stock-based compensation expense	43			43			43
Distribution to noncontrolling interest holders	(6)									(6)
Vesting of restricted stock units, net of shares withheld for employee taxes (in shares)					277,000
Vesting of restricted stock units, net of shares withheld for employee taxes	(6)			(6)			(6)
Conversion of Class B shares to Class A shares (in shares)					14,321,000	14,321,000
Shares issued under Omnibus incentive plan (in shares)		463,826			187,000
Other	(1)			(4)			(4)			3
Ending balance (in shares) at Sep. 30, 2022					137,199,000	377,650,000
Ending balance at Sep. 30, 2022	168			152	$ 0	$ 1	1,975	(1,477)	(347)	16
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	439			430				430		9
Other comprehensive (loss) income, net of tax	25			25					25
Dividends	(340)			(340)				(340)
Stock-based compensation expense	39			39			39
Distribution to noncontrolling interest holders	(12)									(12)
Acquisition of noncontrolling interests	112									112
Shares issued under the plan (in shares)					869,008
Shares issued under Omnibus incentive plan (in shares)		276,516			277,000
Other	(1)			1			1			(2)
Ending balance (in shares) at Sep. 30, 2023		138,345,000	377,650,000		138,345,000	377,650,000
Ending balance at Sep. 30, 2023	430			307	$ 0	$ 1	2,015	(1,387)	(322)	123
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	478			435				435		43
Other comprehensive (loss) income, net of tax	75			75					75
Dividends	(361)			(361)				(361)
Stock-based compensation expense	67			67			67
Distribution to noncontrolling interest holders	(8)									(8)
Acquisition of noncontrolling interests	(1)									(1)
Shares issued under the plan (in shares)					1,738,016	2,270,136
Exchange of Class B shares for Class A shares (in shares)					2,270,000	2,270,000
Shares issued under Omnibus incentive plan (in shares)		206,298			206,000
Shares issued under Omnibus Incentive Plan	(5)			(5)			(5)
Ending balance (in shares) at Sep. 30, 2024		142,559,000	375,380,000		142,559,000	375,380,000
Ending balance at Sep. 30, 2024	$ 675			$ 518	$ 0	$ 1	$ 2,077	$ (1,313)	$ (247)	$ 157