Segments and Related Information (Foreign Operations) (Narrative) (Details) - USD ($) $ in Thousands			3 Months Ended
Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2016	Mar. 31, 2015
Segments and Related Information [Line Items]
Revenue			$ 974,225	$ 1,003,268
Property and equipment, net	$ 547,957	$ 558,667	547,957
Intangible assets and goodwill, net	$ 1,189,500	$ 1,187,900	1,189,500
Accounts Receivable, Net, Less Billings in Excess of Costs and Earnings [Member] \| Credit Concentration Risk [Member] \| Foreign Customers [Member]
Segments and Related Information [Line Items]
Concentration risk, percentage of total	13.00%	17.00%
United States [Member]
Segments and Related Information [Line Items]
Revenue			890,700	820,200
Property and equipment, net	$ 453,800	$ 464,600	453,800
Intangible assets and goodwill, net	1,100,000	1,100,000	1,100,000
Foreign Operations [Member]
Segments and Related Information [Line Items]
Revenue			83,500	$ 183,100
Property and equipment, net	94,200	94,100	94,200
Intangible assets and goodwill, net	$ 113,700	$ 107,300	$ 113,700

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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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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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
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-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 13
-Subparagraph a
-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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