Guarantees (Details) (USD $)	12 Months Ended
	Jan. 29, 2012		Jan. 30, 2011		Jan. 31, 2010
Notes to financial statements [Abstract]
Payments related to warranty accrual	$ 73,300,000		$ 149,800,000		$ 196,000,000
Estimated product warranty liabilities
Balance at beginning of period	107,896,000		92,655,000		150,631,000
Additions (1)	7,329,000	[1]	194,108,000	[1]	170,715,000	[1]
Deductions (2)	(96,819,000)	[2]	(178,867,000)	[2]	(228,691,000)	[2]
Balance at end of period	18,406,000		107,896,000		92,655,000
Cumulative warranty charge	475,900,000
Cumulative net warranty charge against cost of revenue	466,400,000
Incremental repair and replacement costs for the weak die/packaging material set			$ 186,200,000		$ 164,500,000

[1] Includes $186.2 million and $164.5 million for fiscal years 2011 and 2010, respectively, for incremental repair and replacement costs from a weak die/packaging material set.

[2] Includes $73.3 million, $149.8 million and $196.0 million for fiscal years 2012, 2011 and 2010, respectively, in payments related to the warranty accrual associated with incremental repair and replacement costs from a weak die/packaging material set.