Segment Information (Details 1) (USD $) In Millions	12 Months Ended
Apr. 30, 2011	Apr. 30, 2010	Apr. 30, 2009
Net sales by geographic region:
Net Sales, United States	$ 1,525	$ 1,529	$ 1,542
Net Sales, geographic region	3,404	3,226	3,192
Europe
Net sales by geographic region:
Net Sales, Europe and Other	909	879	892
Other
Net sales by geographic region:
Net Sales, Europe and Other	$ 970	$ 818	$ 758

Revenues from external customers attributed to all foreign countries in total from which the entity derives revenues.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 131
-Paragraph 38
-Subparagraph a(2)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6534315&loc=d3e9038-108599

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Period Type:	duration