Financing Arrangements - Long-Term Debt (Details) - USD ($) $ in Millions	9 Months Ended
Jan. 24, 2020	Apr. 26, 2019
Debt Instrument [Line Items]
Current debt obligations	$ 844	$ 838
Long-term debt
Debt (discount) premium, net	(15)	29
Deferred financing costs	(106)	(104)
Long-term debt	$ 24,732	24,486
Senior notes \| 0.000 percent two-year 2019 senior notes
Long-term debt
Stated interest rate	0.00%
Term of debt instrument	2 years
Long-term debt, gross	$ 1,662	1,681
Senior notes \| Floating rate two-year 2019 senior notes
Long-term debt
Term of debt instrument	2 years
Long-term debt, gross	$ 831	560
Senior notes \| 4.125 percent ten-year 2011 senior notes
Long-term debt
Stated interest rate	4.125%
Term of debt instrument	10 years
Long-term debt, gross	$ 0	500
Senior notes \| 3.150 percent seven-year 2015 senior notes
Long-term debt
Stated interest rate	3.15%
Term of debt instrument	7 years
Long-term debt, gross	$ 1,534	2,500
Senior notes \| 3.125 percent ten-year 2012 senior notes
Long-term debt
Stated interest rate	3.125%
Term of debt instrument	10 years
Long-term debt, gross	$ 0	675
Senior notes \| 3.200 percent ten-year 2012 CIFSA senior notes
Long-term debt
Stated interest rate	3.20%
Term of debt instrument	10 years
Long-term debt, gross	$ 650	650
Senior notes \| 0.375 percent four-year 2019 senior notes
Long-term debt
Stated interest rate	0.375%
Term of debt instrument	4 years
Long-term debt, gross	$ 1,662	1,681
Senior notes \| 2.750 percent ten-year 2013 senior notes
Long-term debt
Stated interest rate	2.75%
Term of debt instrument	10 years
Long-term debt, gross	$ 530	530
Senior notes \| 0.000 percent four-year 2019 senior notes
Long-term debt
Stated interest rate	0.00%
Term of debt instrument	4 years
Long-term debt, gross	$ 831	0
Senior notes \| 2.950 percent ten-year 2013 CIFSA senior notes
Long-term debt
Stated interest rate	2.95%
Term of debt instrument	10 years
Long-term debt, gross	$ 310	310
Senior notes \| 3.625 percent ten-year 2014 senior notes
Long-term debt
Stated interest rate	3.625%
Term of debt instrument	10 years
Long-term debt, gross	$ 432	850
Senior notes \| 3.500 percent ten-year 2015 senior notes
Long-term debt
Stated interest rate	3.50%
Term of debt instrument	10 years
Long-term debt, gross	$ 2,700	4,000
Senior notes \| 0.250 percent seven-year 2019 senior notes
Long-term debt
Stated interest rate	0.25%
Term of debt instrument	7 years
Long-term debt, gross	$ 1,108	0
Senior notes \| 1.125 percent eight-year 2019 senior notes
Long-term debt
Stated interest rate	1.125%
Term of debt instrument	8 years
Long-term debt, gross	$ 1,662	1,681
Senior notes \| 3.350 percent ten-year 2017 senior notes
Long-term debt
Stated interest rate	3.35%
Term of debt instrument	10 years
Long-term debt, gross	$ 368	850
Senior notes \| 1.625 percent twelve-year 2019 senior notes
Long-term debt
Stated interest rate	1.625%
Term of debt instrument	12 years
Long-term debt, gross	$ 1,108	1,121
Senior notes \| 1.000 percent thirteen-year 2019 senior notes
Long-term debt
Stated interest rate	1.00%
Term of debt instrument	13 years
Long-term debt, gross	$ 1,108	0
Senior notes \| 4.375 percent twenty-year 2015 senior notes
Long-term debt
Stated interest rate	4.375%
Term of debt instrument	20 years
Long-term debt, gross	$ 1,931	2,382
Senior notes \| 6.550 percent thirty-year 2007 CIFSA senior notes
Long-term debt
Stated interest rate	6.55%
Term of debt instrument	30 years
Long-term debt, gross	$ 253	284
Senior notes \| 2.250 percent twenty-year 2019 senior notes
Long-term debt
Stated interest rate	2.25%
Term of debt instrument	20 years
Long-term debt, gross	$ 1,108	1,121
Senior notes \| 6.500 percent thirty-year 2009 senior notes
Long-term debt
Stated interest rate	6.50%
Term of debt instrument	30 years
Long-term debt, gross	$ 158	183
Senior notes \| 5.550 percent thirty-year 2010 senior notes
Long-term debt
Stated interest rate	5.55%
Term of debt instrument	30 years
Long-term debt, gross	$ 224	306
Senior notes \| 1.500 percent twenty-year 2019 senior notes
Long-term debt
Stated interest rate	1.50%
Term of debt instrument	20 years
Long-term debt, gross	$ 1,108	0
Senior notes \| 4.500 percent thirty-year 2012 senior notes
Long-term debt
Stated interest rate	4.50%
Term of debt instrument	30 years
Long-term debt, gross	$ 105	129
Senior notes \| 4.000 percent thirty-year 2013 senior notes
Long-term debt
Stated interest rate	4.00%
Term of debt instrument	30 years
Long-term debt, gross	$ 305	325
Senior notes \| 4.625 percent thirty-year 2014 senior notes
Long-term debt
Stated interest rate	4.625%
Term of debt instrument	30 years
Long-term debt, gross	$ 127	177
Senior notes \| 4.625 percent thirty-year 2015 senior notes
Long-term debt
Stated interest rate	4.625%
Term of debt instrument	30 years
Long-term debt, gross	$ 1,813	1,963
Senior notes \| 1.750 percent thirty-year 2019 senior notes
Long-term debt
Stated interest rate	1.75%
Term of debt instrument	30 years
Long-term debt, gross	$ 1,108	0
Bank borrowings
Long-term debt
Long-term debt, gross	70	83
Finance lease obligations
Long-term debt
Finance lease obligations	47
Finance lease obligations		10
Interest rate swaps
Long-term debt
Interest rate swaps	$ 0	$ 9

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date.

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