Shareholders' Equity - Stock Repurchase Program (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Jul. 25, 2020	Jul. 27, 2019	Jul. 28, 2018
Stockholders' Equity Note [Abstract]
Shares (in shares)	59	418	432
Weighted-Average Price per Share (in dollars per share)	$ 44.36	$ 49.22	$ 40.88
Amount	$ 2,619	$ 20,577	$ 17,661

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Balance Type:	debit
Period Type:	duration