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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The expense recognized in the current period that allocates the cost of nonproduction tangible assets over their useful lives.

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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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Composition of Certain Financial Statement Captions (Property And Equipment) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Property and Equipment [Line Items]
Property and Equipment, gross	$ 533,403		$ 514,312
Less: Accumulated depreciation	(360,148)		(353,453)
Property and Equipment, net	173,255		160,859
Depreciation expense	7,473	$ 7,331
Buildings
Property and Equipment [Line Items]
Property and Equipment, gross	162,891		162,882
Equipment
Property and Equipment [Line Items]
Property and Equipment, gross	131,660		123,945
Land
Property and Equipment [Line Items]
Property and Equipment, gross	10,830		10,830
Purchased software
Property and Equipment [Line Items]
Property and Equipment, gross	144,342		143,705
Furniture and fixtures
Property and Equipment [Line Items]
Property and Equipment, gross	19,902		18,835
Leasehold improvements
Property and Equipment [Line Items]
Property and Equipment, gross	19,695		20,700
Construction in progress
Property and Equipment [Line Items]
Property and Equipment, gross	$ 44,083		$ 33,415