Intangible Assets (Details) (USD $)	3 Months Ended		6 Months Ended
	Jul. 31, 2011	Aug. 01, 2010	Jul. 31, 2011	Aug. 01, 2010	Jan. 30, 2011
Amortizable intangible assets components [Line Items]
Gross Carrying Amount	$ 523,887,000		$ 523,887,000		$ 428,019,000
Accumulated Amortization	(165,751,000)		(165,751,000)		(139,274,000)
Net Carrying Amount	358,136,000		358,136,000		288,745,000
Amortization expense associated with intangible assets
Amortization expense	15,600,000.0	7,200,000.0	26,500,000.0	14,300,000.0
Future amortization expense associated with intangible assets
Remainder of fiscal 2012			32,400,000.0
Fiscal 2013			57,400,000.0
Fiscal 2014			52,800,000.0
Fiscal 2015			52,700,000.0
Fiscal 2016			47,400,000.0
Fiscal 2017 and fiscal years subsequent of fiscal 2017			115,500,000.0
Technology Licenses
Amortizable intangible assets components [Line Items]
Gross Carrying Amount	319,445,000		319,445,000		320,477,000
Accumulated Amortization	(79,338,000)		(79,338,000)		(62,791,000)
Net Carrying Amount	240,107,000		240,107,000		257,686,000
Acquisition-related intangible assets
Amortizable intangible assets components [Line Items]
Gross Carrying Amount	172,039,000		172,039,000		75,339,000
Accumulated Amortization	(68,496,000)		(68,496,000)		(61,114,000)
Net Carrying Amount	103,543,000		103,543,000		14,225,000
Patents
Amortizable intangible assets components [Line Items]
Gross Carrying Amount	32,403,000		32,403,000		32,203,000
Accumulated Amortization	(17,917,000)		(17,917,000)		(15,369,000)
Net Carrying Amount	$ 14,486,000		$ 14,486,000		$ 16,834,000