Merger - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended	3 Months Ended			10 Months Ended
	Sep. 30, 2011	Sep. 30, 2011 Recorded Music [Member]	Sep. 30, 2011 Music Publishing [Member]	Sep. 30, 2011 Successor [Member]	Jul. 19, 2011 Predecessor [Member]
Business Acquisition [Line Items]
Merger transaction costs	$ 53			$ 10	$ 43
Goodwill allocation recorded		$ 908	$ 464