Investments in Affiliates (Narrative) (Details) $ in Thousands	1 Months Ended	3 Months Ended				9 Months Ended
	Apr. 30, 2014 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Mar. 31, 2009 USD ($)	Sep. 30, 2015 USD ($) item	Sep. 30, 2014 USD ($)	Dec. 31, 2009 USD ($)	Dec. 31, 2008 USD ($)
Telesat Holdings Inc [Member]
Investments in and Advances to Affiliates [Line Items]
Economic interest in affiliates		62.80%	62.80%			62.80%
Voting interest in affiliate		32.70%	32.70%			32.70%
Equity method investment unrecognized loss in equity		$ 37,400				$ 37,400
Equity method investment unrecognized gain in other comprehensive income						13,800
Capital expenditures						$ 57,000	$ 59,800
XTAR, LLC [Member]
Investments in and Advances to Affiliates [Line Items]
Percentage of ownership interest		56.00%				56.00%
Equity Method Investment, Other than Temporary Impairment		$ 8,000	$ 18,700
Lease obligation		26,000				$ 26,000
Maximum annual lease obligation		28,000				28,000
Lease agreement, past due									$ 32,300
Lease agreement, deferred amount								$ 6,700
Repayment term past due and deferred lease obligation, years					12 years
Deferred lease obligation, annual payment					$ 5,000
Discount rate for prepayment of restructured past due and deferred lease obligation					9.00%
Cumulative payments of restructured past due and deferred lease obligation						29,200
EquityMethodInvestmentInvesteePastDueLiability		$ 14,500	$ 5,400			$ 14,500
6% Senior Notes Due May 2017 [Member] | Telesat Holdings Inc [Member]
Investments in and Advances to Affiliates [Line Items]
Interest on notes		6.00%				6.00%
Interest expense multiplier to determine EBITDA available for dividend distribution | item						1.40
Transaction, Consulting Agreement [Member] | Telesat Holdings Inc [Member]
Investments in and Advances to Affiliates [Line Items]
Transaction income during the period		$ 1,250		$ 1,250		$ 3,800	3,800
Transaction payments received during the period						3,600	3,600
Transaction, Tax Indemnification [Member] | Telesat Holdings Inc [Member]
Investments in and Advances to Affiliates [Line Items]
Transaction payments received during the period	$ 5,400
Equity method investment reduction carrying value	$ 5,000
Other Comprehensive Income (Loss) [Member] | Telesat Holdings Inc [Member]
Investments in and Advances to Affiliates [Line Items]
Error corrections and prior period adjustments		5,300		1,500		5,300	400
Investment Income [Member] | Telesat Holdings Inc [Member]
Investments in and Advances to Affiliates [Line Items]
Error corrections and prior period adjustments		$ (3,500)		$ (1,500)		$ (3,500)	$ 300