Stockholders' Equity (Contracts' Value Allocated To Cost Of Shares Repurchased And To The Value Of The ASR Forward Contracts) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Oct. 28, 2011
Accelerated Share Repurchases [Line Items]
Repurchase and retirement of common stock, shares	(14.4)
Repurchase and retirement of common stock	$ (590.8)
Value of ASR forward contracts	(9.2)
Total cash payment	(600.0)
Shares Of Common Stock [Member]
Accelerated Share Repurchases [Line Items]
Repurchase and retirement of common stock, shares	(14.4)
Total cash payment, shares	(14.4)
Additional Paid-In Capital [Member]
Accelerated Share Repurchases [Line Items]
Repurchase and retirement of common stock	(123.7)
Value of ASR forward contracts	(9.2)
Total cash payment	(132.9)
Retained Earnings [Member]
Accelerated Share Repurchases [Line Items]
Repurchase and retirement of common stock	(467.1)
Total cash payment	$ (467.1)

Accelerated share repurchases settlement payment or receipt, shares.

No definition available.

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- Definition

Value of accelerated share repurchase agreement forward contract value.

+ References

No definition available.

+ Details

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- Details

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- Definition

Dollar amount of the cash payment to or cash received from the bank; or the stock issuance to (stock received from) the bank in the settlement of the accelerated share repurchase agreement.

+ References

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

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 99-7

-Paragraph 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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Balance Type:	debit
Period Type:	instant

- Definition

Number of shares that have been repurchased and retired during the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 12

-Paragraph 10

-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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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- Definition

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

+ References

+ Details

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