Subsequent Event (Details) (USD $) In Millions	12 Months Ended	0 Months Ended
Apr. 29, 2011	Apr. 30, 2010	May 06, 2011 Maximum [Member]	May 06, 2011 Minimum [Member]	May 06, 2011 LSI Corporation (LSI) [Member]
Net revenues	$ 5,823.8	$ 4,605.7
Net income	606.8	366.9
Purchase price cash component					480.0
Customer warranties			14.5	13.0
Purchase price allocated to identifiable intangible assets			350.0	250.0
Pro forma adjustment for business combination acquisition related costs	$ 2.5

Business Acquisition Cost Of Acquired Entity Purchase Price Adjustment From Seller For Warranty

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- Definition

Business Acquisition Purchase Price Allocation Intangible Assets Excluding Goodwill

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Pro Forma Adjustment For Business Combination Acquisition Related Costs

+ Details

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- Definition

Amount of cash paid to acquire the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph f(1)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=6909870&loc=d3e1392-128463

+ Details

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

+ Details

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