Schedule of Derivatives Designated as Hedging Instruments (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended		12 Months Ended
	Sep. 30, 2012	Sep. 25, 2011	Dec. 25, 2011
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized In Income	$ 0.8	$ (1.5)
Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount	295.9		318.3
Fair Value	1.8		(5.5)
Amount of Gain (Loss) Recognized In AOCI	1.8		(5.5)
Amount of Gain (Loss) Recognized In Income	1.2	1.5
Amount of Gain (Loss) Reclassified from AOCI	1.2	1.5
Designated as Hedging Instrument | Derivatives For Forecasted Revenues | Current Assets
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount			60.3
Fair Value			0.9
Amount of Gain (Loss) Recognized In AOCI			0.9
Designated as Hedging Instrument | Derivatives For Forecasted Revenues | Current Liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount	50.9
Fair Value	(0.3)
Amount of Gain (Loss) Recognized In AOCI	(0.3)
Designated as Hedging Instrument | Derivatives For Forecasted Expenses | Current Assets
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount	245.0		33.6
Fair Value	2.1
Amount of Gain (Loss) Recognized In AOCI	2.1
Designated as Hedging Instrument | Derivatives For Forecasted Expenses | Current Liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Notional Amount			224.4
Fair Value			(6.4)
Amount of Gain (Loss) Recognized In AOCI			(6.4)
Designated as Hedging Instrument | Foreign Currency Contracts | Revenue
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized In Income	1.2	(3.0)
Amount of Gain (Loss) Reclassified from AOCI	1.2	(3.0)
Designated as Hedging Instrument | Foreign Currency Contracts | Expenses
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized In Income		4.5
Amount of Gain (Loss) Reclassified from AOCI		$ 4.5