Financing Arrangements (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Jan. 25, 2012	Jan. 26, 2011	Apr. 27, 2011
Transfers and Servicing [Abstract]
Financing Arrangement Term	3 years
Amount of accounts receivable securitization program	$ 175
Initial cash funding under receivable securitization program	137.0	134.2
Cash proceeds from receivables sold through accounts receivable securitization program	108.0	50.0
Fair value of deferred purchase price	84.4		173.9
Cash proceeds from deferred purchase price of accounts receivable securitization program	89.5	21.9
Trade receivables sold without recourse	$ 150		$ 146

The increase (decrease) during the reporting period in the value of the assets created and retained during the securitization of trade receivables, which are not otherwise defined in the taxonomy.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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