Goodwill And Intangible Assets (Summary Of Acquired Intangible Assets) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Apr. 01, 2012	Dec. 25, 2011
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	$ 359.3	$ 359.3
Identifiable intangible assets, Accumulated Amortization	(298.7)	(293.9)
Goodwill	169.3	169.3
Identifiable intangible assets, including goodwill, Gross Carrying Amount	528.6	528.6
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	250.7	250.7
Identifiable intangible assets, Accumulated Amortization	(218.2)	(214.3)
Customer Base [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	81.6	81.6
Identifiable intangible assets, Accumulated Amortization	(69.1)	(68.5)
Core Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	15.7	15.7
Identifiable intangible assets, Accumulated Amortization	(3.0)	(2.7)
Identifiable intangible assets, Period of Amortization, years	10
In Process R&D [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	2.8	2.8
Identifiable intangible assets, Period of Amortization, years	10
Assembled Workforce [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	1.0	1.0
Identifiable intangible assets, Accumulated Amortization	(1.0)	(1.0)
Identifiable intangible assets, Period of Amortization, years	5
Process Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	1.6	1.6
Identifiable intangible assets, Accumulated Amortization	(1.6)	(1.6)
Identifiable intangible assets, Period of Amortization, years	5
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	5.9	5.9
Identifiable intangible assets, Accumulated Amortization	$ (5.8)	$ (5.8)
Identifiable intangible assets, Period of Amortization, years	4
Minimum [Member] | Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization, years	2
Minimum [Member] | Customer Base [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization, years	8
Maximum [Member] | Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization, years	15
Maximum [Member] | Customer Base [Member]
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization, years	10