Summary of Significant Accounting Policies (Depreciation Period by Type of Assets) (Details)	12 Months Ended
	Jul. 28, 2018
Buildings
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, useful life	25 years
Building improvements
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, useful life	10 years
Leasehold improvements | Maximum
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, useful life	10 years
Computer equipment and related software | Minimum
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, useful life	30 months
Computer equipment and related software | Maximum
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, useful life	36 months
Production, engineering, and other equipment | Maximum
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, useful life	5 years
Furniture and fixtures
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, useful life	5 years