Other Balance Sheet Items (Property And Equipment, Net) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Land	$ 31,141	$ 31,141
Buildings and building improvements	250,431	248,885
Computer equipment and software	415,086	470,237
Capital work in progress	4,330	6,779
Office equipment and furniture	9,179	8,437
Leasehold improvements	1,458	1,458
Total cost	711,625	766,937
Less: accumulated depreciation and amortization	(466,054)	(516,654)
Total property and equipment, net	$ 245,571	$ 250,283

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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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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The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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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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