Financing Arrangements - Carrying Value of Long-Term Debt (Detail) - USD ($) $ in Millions	Apr. 26, 2019	Apr. 27, 2018
Debt Instrument [Line Items]
Total senior notes	$ 1,544	$ 1,541
Less: Current portion of long-term debt	(400)	0
Total long-term debt	1,144	1,541
Senior Notes
Debt Instrument [Line Items]
Total principal amount	1,550	1,550
Unamortized discount and issuance costs	(6)	(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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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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.

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