Investments in Affiliates (Equity Method Investment, Summarized Financial Data) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Telesat Holdings Inc [Member]
Summary Financial Data:
Revenues	$ 177,111	$ 170,501
Operating expenses	(41,672)	(32,569)
Depreciation, amortization and stock-based compensation	(48,497)	(47,013)
Gain (loss) on disposition of long lived asset	(18)	(1,817)
Operating income (loss)	86,924	89,102
Interest expense	(36,793)	(35,202)
Foreign exchange gains (losses)	17,851	135,907
Gains (losses) on financial instruments	(3,613)	(12,617)
Other income (expense)	145	854
Income tax provision	(9,838)	(11,020)
Net income (loss)	54,676	167,024
Current assets	300,287		$ 678,361
Total assets	3,822,364		4,194,006
Current liabilities	136,822		154,173
Long-term debt, including current portion	2,844,622		2,877,950
Total liabilities	3,552,133		3,597,056
Shareholders' equity/Members' equity	270,231		596,950
XTAR, LLC [Member]
Summary Financial Data:
Revenues	3,697	5,878
Operating expenses	(3,981)	(8,255)
Depreciation, amortization and stock-based compensation	(1,658)	(2,192)
Operating income (loss)	(1,942)	(4,569)
Net income (loss)	(3,273)	$ (5,528)
Current assets	5,713		6,364
Total assets	33,698		36,008
Current liabilities	55,321		53,795
Total liabilities	75,601		75,395
Shareholders' equity/Members' equity	$ (41,903)		$ (39,387)