Summary of Acquired Intangible Assets (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 29, 2015	Dec. 28, 2014
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	$ 365.4	$ 367.0
Goodwill	204.6	209.2
Identifiable intangible assets, Accumulated Amortization	(331.6)	(329.8)
Identifiable intangible assets, including goodwill, Gross Carrying Amount	570.0	576.2
Developed Technology
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	260.3	261.4
Identifiable intangible assets, Accumulated Amortization	(245.9)	(245.3)
Developed Technology | Minimum
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization	8 years
Developed Technology | Maximum
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization	10 years
Customer Base
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	85.7	86.1
Identifiable intangible assets, Accumulated Amortization	(78.2)	(77.4)
Customer Base | Minimum
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization	6 years
Customer Base | Maximum
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization	10 years
Core Technology
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	15.7	15.7
Identifiable intangible assets, Accumulated Amortization	(6.6)	(6.3)
Core Technology | Minimum
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization	10 years
Core Technology | Maximum
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization	15 years
In Process R&D
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Gross Carrying Amount	3.2	3.3
Identifiable intangible assets, Accumulated Amortization	(0.8)	(0.7)
In Process R&D | Minimum
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization	3 years
In Process R&D | Maximum
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization	10 years
Trademarks and trade names
Finite-Lived Intangible Assets [Line Items]
Identifiable intangible assets, Period of Amortization	5 years
Identifiable intangible assets, Gross Carrying Amount	0.5	0.5
Identifiable intangible assets, Accumulated Amortization	$ (0.1)	$ (0.1)