Intangible Assets and Goodwill - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
May. 02, 2015	May. 03, 2014	Apr. 27, 2013
Acquired Finite-Lived Intangible Assets [Line Items]
Impairment losses on unamortizable intangible assets	$ 0	$ 1,602	$ 0

Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16373-109275

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