Warranty Obligation (Details) (USD $) In Millions	3 Months Ended
Jul. 29, 2011	Jul. 30, 2010
Movement In Standard Product Warranty Accrual [Roll Forward]
Balance at the beginning of the period	$ 44	$ 45
Warranty claims provision	6	6
Settlements made	(8)	(6)
Balance at the end of the period	$ 42	$ 45

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 45
-Paragraph 14
-Subparagraph b

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the aggregate decrease in the liability for payments made (in cash or in kind) to satisfy claims under the terms of the standard product warranty. Does not include any increase (decrease) in the liability for payments related to extended product warranties

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 45
-Paragraph 14
-Subparagraph b

+ Details

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- Definition

Represents the aggregate increase in the liability for accruals related to standard product warranties issued during the reporting period. Does not include any increase in the liability for accruals related to extended product warranties

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 45
-Paragraph 14
-Subparagraph b

+ Details

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