Business Combination - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	0 Months Ended	9 Months Ended
Nov. 14, 2012	Jan. 24, 2014	Jan. 25, 2013
Business Acquisition [Line Items]
Business acquisition, cash paid	$ 89.8
Business acquisition, equity	$ 1.2	$ 0	$ 1.2

Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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