Property, Plant and Equipment - Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property Plant And Equipment [Abstract]
Land	$ 4,575	$ 4,575
Building and land improvements	35,105	34,797
Building	68,160	68,157
Furniture and fixtures	19,981	19,959
Computer hardware and software	70,766	68,777
Engineering and other equipment	132,672	130,430
Total property, plant and equipment	331,259	326,695
Less: accumulated depreciation	(266,906)	(258,609)
Total property, plant and equipment, net	$ 64,353	$ 68,086

Amount before accumulated depreciation of building structures held for productive use.

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.

+ References

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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.

+ References

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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.

+ References

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-Publisher FASB
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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.

+ References

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- Definition

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

+ References

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- Definition

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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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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