Income Taxes - Unrecognized Tax Benefit (Detail) - USD ($) $ in Thousands	12 Months Ended
May. 03, 2015	Apr. 27, 2014	Apr. 28, 2013
Income Tax Disclosure [Abstract]
beginning balance	$ 13,740	$ 13,166	$ 12,462
increases from prior period tax positions	588	756	812
decreases from prior period tax positions	(187)	(182)	(108)
ending balance	$ 14,141	$ 13,740	$ 13,166

No definition available.

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

+ Details

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- Definition

Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

+ Details

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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

+ Details

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