Segments and Related Information (Foreign Operations) (Narrative) (Details) - USD ($) $ in Thousands				3 Months Ended											12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	[1]	Jun. 30, 2014	[1]	Mar. 31, 2014	[1]	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment and Related Information [Line Items]
Revenue				$ 1,027,400	$ 1,111,000	$ 1,066,600	$ 1,003,300	$ 1,231,300	$ 1,315,500		$ 1,107,200		$ 957,800		$ 4,208,330	$ 4,611,803	$ 4,324,787
Property and equipment, net	$ 558,667	$ 623,118		558,667				623,118							558,667	623,118
Intangible assets and goodwill, net	$ 1,187,900	$ 1,332,800		1,187,900				1,332,800							1,187,900	1,332,800
Accounts Receivable, Net, Less Billings in Excess of Costs and Earnings [Member] | Credit Concentration Risk [Member] | Foreign Customers [Member]
Segment and Related Information [Line Items]
Concentration risk, percentage of total	17.00%	20.00%	9.00%
United States [Member]
Segment and Related Information [Line Items]
Revenue															3,600,000	3,900,000	4,100,000
Property and equipment, net	$ 464,600	$ 494,100	$ 436,900	464,600				494,100							464,600	494,100	436,900
Intangible assets and goodwill, net	1,100,000	1,100,000	1,000,000	1,100,000				1,100,000							1,100,000	1,100,000	1,000,000
Foreign Operations [Member]
Segment and Related Information [Line Items]
Revenue															574,800	699,900	268,100
Property and equipment, net	94,100	129,000	51,200	94,100				129,000							94,100	129,000	51,200
Intangible assets and goodwill, net	$ 107,300	$ 227,700	$ 92,900	$ 107,300				$ 227,700							$ 107,300	$ 227,700	$ 92,900

[1] Reflects restated data as previously presented in the Company’s 2014 10-K. See Independent Investigation of the Audit Committee and Related Restatements in Note 1 - Business, Basis of Presentation and Significant Accounting Policies.