Employee Benefit Plans - Additional Information - Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Jul. 27, 2019	Jul. 28, 2018	Jul. 29, 2017
Retirement Benefits [Abstract]
Total pretax intrinsic value	$ 149	$ 257	$ 283
In-the-money exercisable stock option (in shares)	2	4
Number exercisable (in shares)	2	4
Weighted- average exercise price (in dollars per share)	$ 6.75	$ 6.84

In The Money Exercisable Stock Option Shares

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- References

No definition available.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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