Stockholders' Equity - Additional Information (Details) - USD ($)	3 Months Ended	9 Months Ended
May 01, 2021	Apr. 25, 2020	May 01, 2021	Apr. 25, 2020	Jul. 25, 2020
Class of Stock [Line Items]
Cash dividends paid per common share (in dollars per share)	$ 0.37	$ 0.36	$ 1.09	$ 1.06
Payments of dividends	$ 1,600,000,000	$ 1,500,000,000	$ 4,601,000,000	$ 4,491,000,000
Remaining authorized repurchase amount	8,700,000,000		8,700,000,000
Stock repurchase program
Class of Stock [Line Items]
Stock repurchases pending settlement	$ 15,000,000		$ 15,000,000		$ 0

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount remaining of a stock repurchase plan authorized.

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