Contractual Maturities of Available for Sale Securities (Detail) (USD $) In Thousands, unless otherwise specified	Jul. 28, 2012	Jan. 28, 2012
Amortized Cost
Due in one year or less	$ 565,566	$ 641,433
Due between one and five years	655,445	816,461
Due over five years	21,999	24,500
Marketable Securities, Debt Maturities, Amortized Cost, Total	1,243,010	1,482,394
Estimated Fair Value
Due in one year or less	566,593	642,317
Due between one and five years	658,976	819,279
Due over five years	20,619	23,215
Estimated Fair Value	$ 1,246,188	$ 1,484,811

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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.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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This item represents debt securities, at fair value, 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.

+ References

No definition available.

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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.

+ References

No definition available.

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This item represents debt securities, at fair value, 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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No definition available.

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- Definition

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 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27161-111563

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 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.4)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

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-Section 50

-Paragraph 5

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-URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27232-111563

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