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Composition of Certain Financial Statement Captions (Property And Equipment) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	$ 567,691	$ 514,312
Less: Accumulated depreciation	(378,639)	(353,453)
Property and Equipment, net	189,052	160,859
Depreciation expense	30,959	29,436	$ 28,792
Buildings
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	206,151	162,882
Equipment
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	141,820	123,945
Land
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	24,179	10,830
Purchased software
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	147,838	143,705
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	21,439	18,835
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	21,604	20,700
Construction in progress
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	$ 4,660	$ 33,415

X

- 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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- Definition

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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No definition available.

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