Fair Value of Derivative Instruments Reported in Consolidated Balance Sheets (Detail) (USD $) In Millions, unless otherwise specified	Sep. 26, 2014	Sep. 27, 2013
Derivatives Fair Value [Line Items]
Asset Derivatives	$ 1.5
Liability Derivatives		1.1
Foreign Exchange Contract
Derivatives Fair Value [Line Items]
Asset Derivatives	1.5	0
Liability Derivatives	0	1.1
Accrued liabilities
Derivatives Fair Value [Line Items]
Liability derivatives, not designated as hedging instruments	0	0
Prepaid expenses and other current assets
Derivatives Fair Value [Line Items]
Asset derivatives, not designated as hedging instruments	0	0
Derivatives Designated as Hedging Instruments | Accrued liabilities
Derivatives Fair Value [Line Items]
Liability Derivatives	0	1.1
Derivatives Designated as Hedging Instruments | Prepaid expenses and other current assets
Derivatives Fair Value [Line Items]
Asset Derivatives	$ 1.5	$ 0