Employee Benefit Plans - Valuation of Employee Share-Based Awards - Employee Stock Purchase Rights (Details) - Employee Stock Purchase Rights - $ / shares	12 Months Ended
Jul. 27, 2019	Jul. 28, 2018	Jul. 29, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	20.40%	22.10%	24.60%
Risk-free interest rate	1.90%	1.30%	0.70%
Expected dividend	3.00%	3.10%	3.20%
Expected life (in years)	1 year 3 months 18 days	1 year 3 months 18 days	1 year 3 months 18 days
Weighted-average estimated grant date fair value per share (in dollars per share)	$ 9.06	$ 7.48	$ 6.52

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

+ Details

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- Definition

Rate of weighted-average expected volatility for award under share-based payment arrangement.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ 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 (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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