Summary of Investments Gross Unrealized Losses and Fair Value (Detail) (USD $) In Thousands, unless otherwise specified	Feb. 02, 2013	Jan. 28, 2012
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	$ 204,793	$ 254,566
Less than 12 months Unrealized Losses	(452)	(819)
12 months or more Fair Value	16,769	23,215
12 months or more Unrealized Losses	(2,681)	(1,285)
Total Fair Value	221,562	277,781
Total Unrealized Losses	(3,133)	(2,104)
Corporate debt securities
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	141,915	146,963
Less than 12 months Unrealized Losses	(382)	(799)
Total Fair Value	141,915	146,963
Total Unrealized Losses	(382)	(799)
U.S. federal and state debt securities
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	14,677	107,603
Less than 12 months Unrealized Losses	(5)	(20)
Total Fair Value	14,677	107,603
Total Unrealized Losses	(5)	(20)
Auction rate securities
Investments, Unrealized Loss Position [Line Items]
12 months or more Fair Value	16,769	23,215
12 months or more Unrealized Losses	(2,681)	(1,285)
Total Fair Value	16,769	23,215
Total Unrealized Losses	(2,681)	(1,285)
Asset-backed Securities
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	43,882
Less than 12 months Unrealized Losses	(64)
Total Fair Value	43,882
Total Unrealized Losses	(64)
Foreign Government
Investments, Unrealized Loss Position [Line Items]
Less than 12 months Fair Value	4,319
Less than 12 months Unrealized Losses	(1)
Total Fair Value	4,319
Total Unrealized Losses	$ (1)