Contractual interest rate for funds borrowed, under the debt agreement.

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Debt - Debt Redemptions - Additional Information (Detail) - USD ($) $ in Millions				3 Months Ended		12 Months Ended
	Jul. 27, 2016	Jul. 02, 2016	Feb. 16, 2016	Sep. 30, 2016	Mar. 31, 2016	Sep. 30, 2016	Sep. 30, 2014	Sep. 30, 2015
Debt Instrument [Line Items]
Outstanding senior notes				$ 2,812.0		$ 2,812.0		$ 2,994.0
Loss on extinguishment of debt				$ (14.0)	$ (4.0)	(18.0)	$ (141.0)
13.75% Senior Notes due 2019
Debt Instrument [Line Items]
Redemption of senior notes						$ 150.0
Interest rate				13.75%		13.75%	13.75%	13.75%
Holdings Company \| 13.75% Senior Notes due 2019
Debt Instrument [Line Items]
Redemption of senior notes		$ 100.0	$ 50.0
Outstanding senior notes			$ 150.0					$ 150.0
Interest rate			13.75%	13.75%		13.75%		13.75%
Loss on extinguishment of debt		$ (10.0)	$ (5.0)
WMG Acquisition Corp.
Debt Instrument [Line Items]
Loss on extinguishment of debt	$ 4.0
WMG Acquisition Corp. \| Revolving Credit Facility
Debt Instrument [Line Items]
Prepayment of senior term loan facility	$ 295.5