Cash, Cash Equivalents and Marketable Securities - Additional Information (Detail) - USD ($)	6 Months Ended
Aug. 01, 2015	Aug. 02, 2014
Cash and Cash Equivalents [Abstract]
Effective maturity period	Two years or less
Realized loss for other-than-temporary impairments	$ 0	$ 0

This element represents the amount of loss recognized for other than temporary impairments (OTTI) of investments in debt and equity securities.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.M)

-URI http://asc.fasb.org/extlink&oid=27011274&loc=d3e87990-122713

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