Financing Arrangements - Carrying Value of Long-Term Debt (Detail) - USD ($) $ in Millions	Jul. 27, 2018	Apr. 27, 2018
Debt Instrument [Line Items]
Total long-term debt	$ 1,542	$ 1,541
Senior Notes
Debt Instrument [Line Items]
Total principal amount	1,550	1,550
Unamortized discount and issuance costs	(8)	(9)
Senior Notes \| Due September 2019
Debt Instrument [Line Items]
Total principal amount	$ 400	$ 400
Debt Instrument, Effective Interest Rate	2.32%	2.32%
Senior Notes \| Due June 2021
Debt Instrument [Line Items]
Total principal amount	$ 500	$ 500
Debt Instrument, Effective Interest Rate	3.54%	3.54%
Senior Notes \| Due December 2022
Debt Instrument [Line Items]
Total principal amount	$ 250	$ 250
Debt Instrument, Effective Interest Rate	3.43%	3.43%
Senior Notes \| Due September 2024
Debt Instrument [Line Items]
Total principal amount	$ 400	$ 400
Debt Instrument, Effective Interest Rate	3.42%	3.42%

Face (par) amount of debt instrument at time of issuance.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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