Goodwill and Intangible Assets - Changes in Goodwill for Each Reportable Segment (Detail) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015
Goodwill [Line Items]
Beginning balance	$ 1,632	$ 1,661
Acquisitions	13	3
Dispositions	(12)
Other adjustments	(6)	(32)
Ending balance	1,627	1,632
Recorded Music
Goodwill [Line Items]
Beginning balance	1,168	1,197
Acquisitions	13	3
Dispositions	(12)
Other adjustments	(6)	(32)
Ending balance	1,163	1,168
Music Publishing
Goodwill [Line Items]
Beginning balance	464	464
Ending balance	$ 464	$ 464

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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