Shareholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Oct. 26, 2019	Oct. 27, 2018	Jul. 27, 2019
Class of Stock [Line Items]
Cash dividends paid per common share (in dollars per share)	$ 0.35	$ 0.33
Payments of dividends	$ 1,486	$ 1,500
Remaining authorized repurchase amount	12,700
Stock repurchase program
Class of Stock [Line Items]
Stock repurchases pending settlement	$ 24		$ 40

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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Aggregate dividends paid during the period for each share of common stock outstanding.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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Amount remaining of a stock repurchase plan authorized.

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