Reconciliation of Operating Income from Reportable Segments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Jan. 31, 2015	Jan. 25, 2014	Jan. 31, 2015	Jan. 25, 2014
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Reportable segments operating profit	$ 149,521us-gaap_OperatingIncomeLoss	$ 118,716us-gaap_OperatingIncomeLoss	$ 147,163us-gaap_OperatingIncomeLoss	$ 76,757us-gaap_OperatingIncomeLoss
Interest expense, net and amortization of deferred financing costs	3,552	7,761	14,774	22,868
Consolidated income before taxes	$ 145,969	$ 110,955	$ 132,389	$ 53,889

Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Period Type:	duration