Goodwill, Regulatory Authorizations and Other Intangible Assets - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
	Jan. 31, 2019	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Sep. 30, 2017
Finite-Lived Intangible Assets [Line Items]
Amortization expense			$ 43,000	$ 47,000	$ 54,000
Loss from foreign currency transactions			6,464
Finite lives
Finite-Lived Intangible Assets [Line Items]
Amortization expense			$ 5,000	$ 5,000	$ 5,000
Contractual Rights
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets						$ 6,000
Intangible asset impairment		$ 6,000
Subsequent Event
Finite-Lived Intangible Assets [Line Items]
Loss on impairment of asset	$ 33,000
Loss from foreign currency transactions	$ 32,000