Short-term Borrowings and Long-term Debt (Schedule of Long-term Debt Instruments) (Details) - USD ($) $ in Millions	9 Months Ended
Apr. 26, 2020	Jul. 28, 2019
Debt Instrument [Line Items]
Finance Lease, Liability, Noncurrent	$ 7	$ 3
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	(45)	(49)
Long-term Debt and Lease Obligation, Including Current Maturities	5,912	7,603
Long-term Debt, Current Maturities	721	500
Long-term debt	$ 5,191	7,103
Variable Interest Rate due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis	Variable
Debt Instrument, Maturity Date	Mar. 16, 2020
Long-term Debt, Gross	$ 0	500
Variable Interest Rate due 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis	Variable
Debt Instrument, Maturity Date	Mar. 15, 2021
Long-term Debt, Gross	$ 400	400
Variable Interest Rate Term Loan due 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis	Variable
Debt Instrument, Maturity Date	Mar. 26, 2021
Long-term Debt, Gross	$ 0	499
3.300% notes, due 2021
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.30%
Debt Instrument, Maturity Date	Mar. 15, 2021
Long-term Debt, Gross	$ 321	650
4.250% notes, due 2021
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.25%
Debt Instrument, Maturity Date	Apr. 15, 2021
Long-term Debt, Gross	$ 0	500
8.875% notes, due 2021
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	8.875%
Debt Instrument, Maturity Date	May 01, 2021
Long-term Debt, Gross	$ 200	200
2.500% notes, due 2023
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.50%
Debt Instrument, Maturity Date	Aug. 02, 2022
Long-term Debt, Gross	$ 450	450
3.650% notes, due 2023
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.65%
Debt Instrument, Maturity Date	Mar. 15, 2023
Long-term Debt, Gross	$ 566	1,200
3.950% notes, due 2025
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.95%
Debt Instrument, Maturity Date	Mar. 15, 2025
Long-term Debt, Gross	$ 850	850
3.300% notes, due 2025
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.30%
Debt Instrument, Maturity Date	Mar. 19, 2025
Long-term Debt, Gross	$ 300	300
4.150% notes, due 2028
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.15%
Debt Instrument, Maturity Date	Mar. 15, 2028
Long-term Debt, Gross	$ 1,000	1,000
2.375% notes due 2030
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.375%
Debt Instrument, Maturity Date	Apr. 24, 2030
Long-term Debt, Gross	$ 500	0
3.800% notes, due 2042
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.80%
Debt Instrument, Maturity Date	Aug. 02, 2042
Long-term Debt, Gross	$ 163	400
4.800% notes, due 2048
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.80%
Debt Instrument, Maturity Date	Mar. 15, 2048
Long-term Debt, Gross	$ 700	700
3.125% notes, due 2050
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.125%
Debt Instrument, Maturity Date	Apr. 24, 2050
Long-term Debt, Gross	$ 500	$ 0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, including portion classified as current.

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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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