Shareholders' Equity - Stock Repurchase Program (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
Oct. 26, 2019	Jul. 27, 2019	Apr. 27, 2019	Jan. 26, 2019	Oct. 27, 2018
Stockholders' Equity Note [Abstract]
Shares (in shares)	16	82	116	111	109
Weighted-Average Price per Share (in dollars per share)	$ 48.91	$ 54.99	$ 52.14	$ 45.09	$ 46.01
Amount	$ 768	$ 4,515	$ 6,020	$ 5,016	$ 5,026

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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-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration