Guarantor and Non-Guarantor Subsidiaries Financial Information - Consolidating Balance Sheet (Detail) - USD ($) $ in Millions		Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Current assets:
Cash and equivalents		$ 359	$ 246	$ 157	$ 155
Accounts receivable, net		329	349
Inventories		41	42
Royalty advances expected to be recouped within one year		128	130
Prepaid and other current assets		51	60
Total current assets		908	827
Royalty advances expected to be recouped after one year		196	195
Property, plant and equipment, net		203	220
Goodwill		1,627	1,632	1,661
Intangible assets subject to amortization, net		2,201	2,514
Intangible assets not subject to amortization		116	119
Other assets		118	114
Total assets		5,369	5,621
Current liabilities:
Accounts payable		204	173
Accrued royalties		1,104	1,087
Accrued liabilities		297	296
Accrued interest		38	58
Deferred revenue		178	206
Current portion of long-term debt			13
Other current liabilities		21	24
Total current liabilities		1,842	1,857
Long-term debt	[1]	2,812	2,981
Deferred tax liabilities, net		269	302
Other noncurrent liabilities		236	242
Total liabilities		5,159	5,382
Total Warner Music Group Corp. equity (deficit)		195	221
Noncontrolling interest		15	18
Total equity		210	239	390	743
Total liabilities and equity		5,369	5,621
Eliminations
Current assets:
Investments in and advances to (from) consolidated subsidiaries		(3,718)	(3,552)
Total assets		(3,718)	(3,552)
Current liabilities:
Other current liabilities			(1)
Total current liabilities			(1)
Other noncurrent liabilities			3
Total liabilities			2
Total Warner Music Group Corp. equity (deficit)		(3,718)	(3,554)
Total equity		(3,718)	(3,554)
Total liabilities and equity		(3,718)	(3,552)
Eliminations
Current assets:
Investments in and advances to (from) consolidated subsidiaries		(390)	(597)
Total assets		(390)	(597)
Current liabilities:
Total Warner Music Group Corp. equity (deficit)		(390)	(597)
Total equity		(390)	(597)
Total liabilities and equity		(390)	(597)
WMG Acquisition Corp. | Reportable Legal Entities
Current assets:
Prepaid and other current assets		1	5
Total current assets		1	5
Due (to) from parent companies		750	863
Investments in and advances to (from) consolidated subsidiaries		2,260	2,365
Other assets		37	39
Total assets		3,048	3,272
Current liabilities:
Accrued liabilities			1
Accrued interest		38	48
Current portion of long-term debt			13
Total current liabilities		38	62
Long-term debt		2,812	2,831
Other noncurrent liabilities		3	3
Total liabilities		2,853	2,896
Total Warner Music Group Corp. equity (deficit)		195	376
Total equity		195	376
Total liabilities and equity		3,048	3,272
Guarantor Subsidiaries | Reportable Legal Entities
Current assets:
Cash and equivalents		180	73	26	16
Accounts receivable, net		177	170
Inventories		16	15
Royalty advances expected to be recouped within one year		79	80
Prepaid and other current assets		13	9
Total current assets		465	347
Due (to) from parent companies		(312)	(174)
Investments in and advances to (from) consolidated subsidiaries		1,458	1,187
Royalty advances expected to be recouped after one year		120	120
Property, plant and equipment, net		138	145
Goodwill		1,372	1,379
Intangible assets subject to amortization, net		1,165	1,271
Intangible assets not subject to amortization		71	71
Other assets		62	53
Total assets		4,539	4,399
Current liabilities:
Accounts payable		124	79
Accrued royalties		606	513
Accrued liabilities		112	269
Deferred revenue		143	140
Other current liabilities		3	7
Total current liabilities		988	1,008
Deferred tax liabilities, net		109	110
Other noncurrent liabilities		126	131
Total liabilities		1,223	1,249
Total Warner Music Group Corp. equity (deficit)		3,314	3,149
Noncontrolling interest		2	1
Total equity		3,316	3,150
Total liabilities and equity		4,539	4,399
Non-Guarantor Subsidiaries | Reportable Legal Entities
Current assets:
Cash and equivalents		179	173	131	139
Accounts receivable, net		152	179
Inventories		25	27
Royalty advances expected to be recouped within one year		49	50
Prepaid and other current assets		37	46
Total current assets		442	475
Due (to) from parent companies		(438)	(689)
Royalty advances expected to be recouped after one year		76	75
Property, plant and equipment, net		65	75
Goodwill		255	253
Intangible assets subject to amortization, net		1,036	1,243
Intangible assets not subject to amortization		45	48
Other assets		19	17
Total assets		1,500	1,497
Current liabilities:
Accounts payable		80	94
Accrued royalties		498	574
Accrued liabilities		185	26
Deferred revenue		35	66
Other current liabilities		18	18
Total current liabilities		816	778
Deferred tax liabilities, net		160	192
Other noncurrent liabilities		107	105
Total liabilities		1,083	1,075
Total Warner Music Group Corp. equity (deficit)		404	405
Noncontrolling interest		13	17
Total equity		417	422
Total liabilities and equity		1,500	1,497
WMG Acquisition Corp. Consolidated | Reportable Legal Entities
Current assets:
Cash and equivalents		359	246	$ 157	$ 155
Accounts receivable, net		329	349
Inventories		41	42
Royalty advances expected to be recouped within one year		128	130
Prepaid and other current assets		51	60
Total current assets		908	827
Royalty advances expected to be recouped after one year		196	195
Property, plant and equipment, net		203	220
Goodwill		1,627	1,632
Intangible assets subject to amortization, net		2,201	2,514
Intangible assets not subject to amortization		116	119
Other assets		118	109
Total assets		5,369	5,616
Current liabilities:
Accounts payable		204	173
Accrued royalties		1,104	1,087
Accrued liabilities		297	296
Accrued interest		38	48
Deferred revenue		178	206
Current portion of long-term debt			13
Other current liabilities		21	24
Total current liabilities		1,842	1,847
Long-term debt		2,812	2,831
Deferred tax liabilities, net		269	302
Other noncurrent liabilities		236	242
Total liabilities		5,159	5,222
Total Warner Music Group Corp. equity (deficit)		195	376
Noncontrolling interest		15	18
Total equity		210	394
Total liabilities and equity		5,369	5,616
WMG Holdings Corp. | Reportable Legal Entities
Current assets:
Investments in and advances to (from) consolidated subsidiaries		195	376
Other assets			5
Total assets		195	381
Current liabilities:
Accrued interest			10
Total current liabilities			10
Long-term debt			150
Total liabilities			160
Total Warner Music Group Corp. equity (deficit)		195	221
Total equity		195	221
Total liabilities and equity		195	381
Warner Music Group Corp. | Reportable Legal Entities
Current assets:
Investments in and advances to (from) consolidated subsidiaries		195	221
Total assets		195	221
Current liabilities:
Total Warner Music Group Corp. equity (deficit)		195	221
Total equity		195	221
Total liabilities and equity		$ 195	$ 221

[1] Total long-term debt, including the current portion does not reflect the October 2016 tender offers for, and satisfaction and discharge of, the 6.000% Senior Secured Notes due 2021 and the 6.250% Senior Secured Notes due 2021, the October issuance of 4.125% Senior Secured Notes due 2024 and 4.875% Senior Secured Notes due 2024, the November 2016 Senior Term Loan Credit Agreement Amendment, or the November redemption of the 5.625% Senior Secured Notes due 2022. See “Recent Developments – Tender Offers and Satisfaction and Discharge” and “Liquidity – New Senior Secured Notes.”