Intangible Assets (Details) (USD $)	12 Months Ended
	Jan. 29, 2012	Jan. 30, 2011	Jan. 31, 2010
Amortizable intangible assets components [Line Items]
Gross Carrying Amount	$ 524,425,000	$ 428,019,000
Accumulated Amortization	(198,289,000)	(139,274,000)
Net Carrying Amount	326,136,000	288,745,000
Amortization expense associated with intangible assets
Amortization expense	59,000,000	30,000,000	31,900,000
Future amortization expense associated with intangible assets
Fiscal 2013	56,200,000
Fiscal 2014	51,300,000
Fiscal 2015	51,300,000
Fiscal 2016	46,000,000
Fiscal 2017	33,100,000
Future amortization after year five	88,200,000
Technology Licenses
Amortizable intangible assets components [Line Items]
Gross Carrying Amount	319,930,000	320,477,000
Accumulated Amortization	(99,302,000)	(62,791,000)
Net Carrying Amount	220,628,000	257,686,000
Finite-Lived Intangible Assets, Average Useful Life	7.6	7.6
Acquisition-related intangible assets
Amortizable intangible assets components [Line Items]
Gross Carrying Amount	172,039,000	75,339,000
Accumulated Amortization	(79,261,000)	(61,114,000)
Net Carrying Amount	92,778,000	14,225,000
Finite-Lived Intangible Assets, Average Useful Life	6.0	3.8
Patents
Amortizable intangible assets components [Line Items]
Gross Carrying Amount	32,456,000	32,203,000
Accumulated Amortization	(19,726,000)	(15,369,000)
Net Carrying Amount	$ 12,730,000	$ 16,834,000
Finite-Lived Intangible Assets, Average Useful Life	5.3	5.3