Investments in Affiliates (Equity Method Investment, Summarized Financial Data) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Telesat Holdings Inc [Member]
Summary Financial Data:
Revenues	$ 703,131	$ 751,684	$ 837,440
Operating expenses	(139,141)	(140,706)	(161,944)
Depreciation, amortization and stock-based compensation	(195,781)	(190,985)	(231,849)
Gain (loss) on disposition of long lived asset	(1,937)	(24)	(276)
Operating income (loss)	366,272	419,969	443,371
Interest expense	(145,288)	(138,783)	(182,395)
Loss on refinancing	(12,246)
Foreign exchange gains (losses)	68,719	(426,980)	(232,275)
Gains (losses) on financial instruments	974	7,810	70,872
Other income (expense)	4,590	3,672	2,779
Income tax provision	(58,772)	(74,447)	(60,954)
Net income (loss)	224,249	(208,759)	41,398
Current assets	678,361	568,106
Total assets	4,194,006	4,009,352
Current liabilities	154,173	187,488
Long-term debt, including current portion	2,877,950	2,968,776
Total liabilities	3,597,056	3,635,918
Shareholders' equity/Members' equity	596,950	373,434
XTAR, LLC [Member]
Summary Financial Data:
Revenues	18,550	25,852	29,171
Operating expenses	(24,123)	(31,933)	(31,367)
Depreciation, amortization and stock-based compensation	(8,589)	(8,874)	(9,257)
Operating income (loss)	(14,162)	(14,955)	(11,453)
Net income (loss)	(18,296)	(18,722)	$ (13,835)
Current assets	6,364	7,533
Total assets	36,008	44,793
Current liabilities	53,795	41,712
Total liabilities	75,395	68,126
Shareholders' equity/Members' equity	$ (39,387)	$ (23,333)