Contractual Maturities of Available-For-Sale Securities (Detail) (USD $) In Thousands	Jul. 30, 2011	Jan. 29, 2011
Amortized Cost
Due in one year or less	$ 608,494	$ 560,190
Due between one and five years	922,828	519,262
Due over five years	27,650	27,850
Marketable Securities, Debt Maturities, Amortized Cost, Total	1,558,972	1,107,302
Estimated Fair Value
Due in one year or less	609,216	560,999
Due between one and five years	927,606	521,957
Due over five years	26,070	26,226
Estimated Fair Value	$ 1,562,892	$ 1,109,182

Marketable Securities, Amortized Cost [Abstract]

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This item represents debt securities, at amortized cost, which are expected to mature after five years from the balance sheet date and which are categorized as marketable securities. The amount excludes cash and cash equivalents.

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This item represents debt securities, at fair value, which are expected to mature after five years from the balance sheet date and which are categorized as marketable securities. The amount excludes cash and cash equivalents.

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This item represents the total of all debt securities grouped by maturity dates, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are classified as marketable.

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This item represents debt securities, at amortized cost, which are expected to mature after one year and through five years from the balance sheet date and which are categorized as marketable securities. The amount excludes cash and cash equivalents.

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This item represents debt securities, at amortized cost, which are expected to mature within one year of the balance sheet date and which are categorized as marketable securities. The amount excludes cash and cash equivalents.

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Marketable Securities, Fair Value [Abstract]

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27232-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 115
-Paragraph 19
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27161-111563

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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