Cash, Cash Equivalents and Investments (Details 3) (USD $) In Millions	3 Months Ended
May 01, 2011
Gross Unrealized Losses and the Fair Market Value of Investments
In Loss Position for Less Than 12 Months, Fair Value	$ 127
In Loss Position for Less Than 12 Months, Gross Unrealized Losses	1
Total, Fair Value	127
Total, Gross Unrealized Losses	1
Other debt securities [Member]
Gross Unrealized Losses and the Fair Market Value of Investments
In Loss Position for Less Than 12 Months, Fair Value	127
In Loss Position for Less Than 12 Months, Gross Unrealized Losses	1
Total, Fair Value	127
Total, Gross Unrealized Losses	$ 1

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This item represents the excess of [amortized] cost over fair value of securities in a loss position and which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 03-1
-Paragraph 21
-Subparagraph a(2)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS115-1/124-1
-Paragraph 17
-Subparagraph a(1)

+ Details

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- Definition

This item represents the fair value of securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

+ Details

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- Definition

This item represents the excess of [amortized] cost over fair value of securities that have been in a loss position for less than twelve months for those securities which are categorized neither as held-to-maturity nor trading securities.

+ References

+ Details

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- Definition

This item represents the fair value of securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ References

+ Details

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