Employee Benefit Plans (Additional Information - Valuation of Employee Share-Based Award) (Details) - 2005 Plan	12 Months Ended
Jul. 28, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award requisite service period	3 years
Performance base and Market base RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
PRSU allocation between Financial operating goals and TSR	50.00%
Award requisite service period	3 years
PRSU based on TSR \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	0.00%
PRSU based on TSR \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	150.00%
PRSU based on financial performance metrics \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	0.00%
PRSU based on financial performance metrics \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	150.00%
PRSU based on nonfinancial operating goals \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	0.00%
PRSU based on nonfinancial operating goals \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage	100.00%

PRSU allocation between Financial operating goals and TSR (in percentage)

No definition available.

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

+ Details

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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.

+ Details

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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