Basis of Presentation (Details)	3 Months Ended	9 Months Ended	12 Months Ended
Apr. 29, 2012 week	Jan. 27, 2013 item	Apr. 28, 2013 week	Apr. 29, 2012 week
Basis of Presentation
Number of weeks in fiscal period	14		52	53
Number of reporting segments		1

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

No definition available.

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration