Segments and Related Information (Foreign Operations) (Narrative) (Details) - USD ($) $ in Thousands			3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Segments and Related Information [Line Items]
Revenue			$ 1,003,268	$ 957,818
Property and equipment, net	$ 608,019	$ 623,118	608,019
Intangible assets and goodwill, net	$ 1,306,500	$ 1,332,800	1,306,500
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	25.00%	20.00%
United States [Member]
Segments and Related Information [Line Items]
Revenue			820,200	831,700
Property and equipment, net	$ 491,800	$ 494,100	491,800
Intangible assets and goodwill, net	1,100,000	1,100,000	1,100,000
Foreign Operations [Member]
Segments and Related Information [Line Items]
Revenue			183,100	$ 126,100
Property and equipment, net	116,300	129,000	116,300
Intangible assets and goodwill, net	$ 206,600	$ 227,700	$ 206,600