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Composition of Certain Financial Statement Captions (Property And Equipment) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	$ 514,312	$ 484,069
Less: Accumulated depreciation	(353,453)	(338,206)
Property and Equipment, net	160,859	145,863
Depreciation expense	29,436	28,792	$ 27,311
Buildings
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	162,882	160,796
Equipment
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	123,945	126,954
Land
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	10,830	10,772
Purchased software
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	143,705	139,245
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	18,835	18,103
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	20,700	18,959
Construction in progress
Property, Plant and Equipment [Line Items]
Property and Equipment, gross	$ 33,415	$ 9,240

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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- Definition

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.

+ References

No definition available.

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