For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Carrying amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance.

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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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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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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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Segments and Related Information (Foreign Operations) (Narrative) (Details) - USD ($) $ in Thousands			3 Months Ended		9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segments and Related Information [Line Items]
Revenue			$ 1,698,279	$ 2,016,618	$ 4,684,180	$ 5,473,965
Property and equipment, net	$ 994,193	$ 905,835	994,193		994,193
United States [Member]
Segments and Related Information [Line Items]
Revenue			1,700,000	2,000,000	4,600,000	5,300,000
Property and equipment, net	971,400	874,700	971,400		971,400
Intangible assets and goodwill, net	1,400,000	1,400,000	1,400,000		1,400,000
Foreign Operations [Member]
Segments and Related Information [Line Items]
Revenue			18,200	$ 64,100	77,800	$ 191,000
Property and equipment, net	22,800	31,100	22,800		22,800
Intangible assets and goodwill, net	$ 50,300	$ 56,400	$ 50,300		$ 50,300
Foreign Operations [Member] \| Accounts Receivable, Net, Less Deferred Revenue [Member] \| Geographic Concentration Risk [Member]
Segments and Related Information [Line Items]
Concentration risk, percentage of total	4.00%	5.00%
Govermment [Member] \| Revenue Benchmark [Member] \| Customer Concentration Risk [Member]
Segments and Related Information [Line Items]
Concentration risk, percentage of total			2.00%	1.00%	2.00%	1.00%