Reconciliation of Operating Profit From Reportable Segments to Income (Loss) From Operations Before Taxes in Consolidated Financial Statements (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Jan. 26, 2013	Oct. 27, 2012	Jul. 28, 2012	Apr. 28, 2012	Jan. 28, 2012	Oct. 29, 2011	Jul. 30, 2011	Apr. 27, 2013	Apr. 28, 2012	Apr. 30, 2011
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Reportable segments operating loss	$ 3,657	$ 8,929	$ (52,285)	$ (68,173)	$ 91,100	$ (972)	$ (76,558)	$ (220,004)	$ (54,603)	$ (56,799)
Interest expense, net and amortization of deferred financing costs	8,772	8,122	8,941	(8,629)	(8,773)	(8,460)	(9,442)	(35,345)	(35,304)	(57,350)
Consolidated loss before taxes	$ (5,115)	$ 807	$ (61,226)	$ (76,802)	$ 82,327	$ (9,432)	$ (86,000)	$ (255,349)	$ (89,907)	$ (114,149)

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=6881521&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Subparagraph 1(i)

-Article 4

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration