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Aggregate notional amount of foreign currency exchange rate derivatives. Notional amount refers to the number of currency units specified in the foreign currency derivative contract.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

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- Definition

Aggregate notional amount of interest rate derivatives, which relates to the currency amount specified in the interest rate derivative instruments.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5580258-113959

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- Definition

Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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- Definition

The pre-tax gain or loss recognized upon settlement of treasury lock contracts during the period. The gain (loss) will be reclassified ratably as a decrease (increase) to interest expense over the term of the related debt.

+ References

No definition available.

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Derivative Financial Instruments (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jan. 27, 2012	Jul. 27, 2012 Foreign Currency Contracts Maturing In 2012 [Member]	Jul. 26, 2013 Foreign Currency Contracts Maturing In 2013 [Member]	Jul. 27, 2012 Foreign Currency Contracts Maturing In 2013 [Member]	Jul. 26, 2013 Foreign Currency Contracts Maturing In 2014 [Member]	Jul. 26, 2013 Treasury Lock Contracts [Member]	Jul. 27, 2012 Treasury Lock Contracts [Member]	Jan. 27, 2012 Treasury Lock Contracts [Member]	Jan. 27, 2012 Senior Notes Due 2022 At 4.20% [Member]
Derivative [Line Items]
Notional amount of foreign currency contracts		$ 3,249	$ 2,895	$ 2,786	$ 2,572
Notional amount of interest rate derivatives						0	0	200,000
Settlement of treasury lock contracts	(27,875)
Unsecured senior notes									$ 400,000