Selected Financial Statement Data Property and Equipment (Details) - USD ($) $ in Thousands	Aug. 03, 2019	Apr. 27, 2019
Property, Plant and Equipment [Line Items]
Land	$ 1,754	$ 1,738
Buildings	66,731	66,403
Machinery and equipment	99,055	96,486
Office furniture and equipment	6,145	6,195
Computer software and hardware	53,611	55,460
Equipment held for rental	287	287
Demonstration equipment	7,172	7,422
Transportation equipment	7,943	7,715
Property, Plant and Equipment, Gross	242,698	241,706
Less accumulated depreciation	175,991	176,392
Property and equipment, net	$ 66,707	$ 65,314

Gross amount, as of the balance sheet date, of long-lived, depreciable equipment used for demonstration.

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- Definition

Gross amount, as of the balance sheet date, of long-lived, depreciable equipment held for rental.

+ References

No definition available.

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- Definition

Gross amount, as of the balance sheet date, of long-lived, depreciable equipment used for transportation.

+ References

No definition available.

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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- Definition

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

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- Definition

Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

+ References

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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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.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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