Fair Market Values for Cash and Marketable Securities (Detail) (USD $) In Thousands, unless otherwise specified	Jul. 28, 2012	Jan. 28, 2012	Jul. 30, 2011	Jan. 29, 2011
Cash and cash equivalents:
Cash and cash equivalents	$ 696,077	$ 719,545	$ 389,299	$ 667,593
Short-term investments:
Short-term investments	5,995	25,499	124,697
Fair Value, Measurements, Recurring
Cash and cash equivalents:
Cash and cash equivalents	696,077	719,545	389,299
Short-term investments:
Short-term investments	5,995	25,499	124,697
Long-term investments:
Long-term investments	254	847	648
Total	702,326	745,891	514,644
Fair Value, Measurements, Recurring | Cash
Cash and cash equivalents:
Cash and cash equivalents	623,277	548,728	287,753
Fair Value, Measurements, Recurring | Money-market
Cash and cash equivalents:
Cash and cash equivalents	44,789	131,785	74,387
Fair Value, Measurements, Recurring | Commercial paper
Cash and cash equivalents:
Cash and cash equivalents	5,000	29,998	23,996
Short-term investments:
Short-term investments			9,997
Fair Value, Measurements, Recurring | Treasury bills
Cash and cash equivalents:
Cash and cash equivalents	23,011	9,034	3,163
Short-term investments:
Short-term investments	5,995	19,999	76,262
Fair Value, Measurements, Recurring | Corporate bonds
Short-term investments:
Short-term investments			16,111
Fair Value, Measurements, Recurring | Term-deposits
Short-term investments:
Short-term investments			15,427
Fair Value, Measurements, Recurring | ARS Call Option
Long-term investments:
Long-term investments	254	847	648
Fair Value, Measurements, Recurring | ARS | State and local government
Short-term investments:
Short-term investments		$ 5,500	$ 6,900