Goodwill, Regulatory Authorizations and Other Intangible Assets - Regulatory Authorizations - (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets Gross [RollForward]
Balance at the beginning of the period		$ 360,835
Balance at the end of the period	$ 361,300	361,300	$ 360,835
Accumulated amortization
Balance at the beginning of the period		(280,101)
Balance at the end of the period	(302,345)	(302,345)	(280,101)
Net
Balance at the beginning of the period		80,734
Balance at the end of the period	58,955	58,955	80,734
Total regulatory authorizations, net
Balance at the beginning of the period		544,633
Additions		(5,097)
Impairment of Intangible Assets (Excluding Goodwill)		(6,000)
Currency Translation Adjustment		3,400
Balance at the end of the period	536,936	536,936	544,633
Amortization of regulatory authorizations		46,900	54,300	$ 71,800
Indefinite Lives
Indefinite lives
Balance at the beginning of the period		471,657
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)		(6,000)
Balance at the end of the period	465,657	465,657	471,657
Contractual Rights [Member]
Indefinite lives
Balance at the beginning of the period	6,000
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)	(6,000)
Finite lives
Finite-Lived Intangible Assets Gross [RollForward]
Balance at the beginning of the period		87,959
Currency Translation Adjustment		4,662
Balance at the end of the period	92,621	92,621	87,959
Accumulated amortization
Balance at the beginning of the period		(14,983)
Additions		(5,097)
Currency Translation Adjustment		(1,262)
Balance at the end of the period	(21,342)	(21,342)	(14,983)
Net
Balance at the beginning of the period		72,976
Additions		(5,097)
Currency Translation Adjustment		3,400
Balance at the end of the period	71,279	71,279	72,976
Total regulatory authorizations, net
Amortization of regulatory authorizations		5,100	4,700	$ 4,700
Brazilian Regulatory Authorization [Member]
Net
Balance at the beginning of the period		38,600
Balance at the end of the period	$ 36,300	$ 36,300	$ 38,600