Fair Value Measurements (Details 2) (USD $)	Feb. 02, 2013	Jan. 28, 2012	Jan. 29, 2011
Amortized Cost
Mature in one year or less	$ 12,771,000	$ 902,000
Mature after one year through five years	5,754,000	18,840,000
Total	18,525,000	19,742,000
Fair Market Value
Mature in one year or less	12,819,000	903,000
Mature after one year through five years	5,760,000	18,935,000
Total Fair Market Value	18,579,000	19,838,000
Changes among the fair value levels
Changes between Level 1 to Level 2, Assets	0	0	0
Changes between Level 2 to Level 1, Assets	0	0	0
Changes between Level 1 to Level 2, Liabilities	0	0	0
Changes between Level 2 to Level 1, Liabilities	$ 0	$ 0	$ 0

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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Amount of held-to-maturity debt securities at fair value maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year.

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Carrying amount of debt securities accounted for as held-to-maturity, net of adjustments including, but not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized, and fair value hedge accounting adjustments, maturing in the next fiscal year through the fifth fiscal year following the latest fiscal year.

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This item represents the aggregate fair value of investments in debt securities as of the balance sheet date and which are categorized as held-to-maturity.

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