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Cash and Cash Equivalents Short-term Investments and Long-term Investments - Additional Information (Detail) (USD $)
3 Months Ended
May 03, 2014
May 04, 2013
Schedule of Available-for-sale Securities [Line Items]    
Sale of available-for-sale securities $ 10,002,000 $ 23,778,000
Purchase of available-for-sale securities 0 15,217,000
Unrecognized gains(losses) for available -for-sale securities $ 0 $ 0