Securities Available for Sale - Additional Information (Detail) (USD $)	9 Months Ended
Nov. 02, 2013
Schedule of Held-to-maturity Securities [Line Items]
Short-term investment securities have original maturities greater than (days)	90 days
Impairment charges on available for sale security	$ 0
Maximum [Member]
Schedule of Held-to-maturity Securities [Line Items]
Anticipated maturity dates range	33 months
Minimum [Member]
Schedule of Held-to-maturity Securities [Line Items]
Anticipated maturity dates range	1 month

The amount by which the fair value of an investment in debt and equity securities categorized as Available-for-sale is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

Name:	us-gaap_OtherThanTemporaryImpairmentLossesInvestmentsAvailableforsaleSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration