Commitments and Contingencies - Narrative Part 2 (Details)				1 Months Ended	3 Months Ended
	Sep. 23, 2016 USD ($)	Aug. 18, 2015 USD ($)	Dec. 23, 2013 USD ($)	Jul. 31, 2009 item	Mar. 31, 2017 USD ($) item	Mar. 31, 2016 USD ($)	Jan. 19, 2017 item $ / item
Loss contingencies
General and administrative expenses					$ 131,035,000	$ 201,001,000
Vermont National Telephone Company [Member]
Loss contingency terms
Recovery amount	$ 10,000,000,000
Satellite transponder guarantees
Loss contingencies
Guarantees for payments					174,000,000
Litigation accrual					$ 0
Technology Development Licensing
Loss contingency terms
Number of reexamination petitions pending before patent and trademark office | item				2
Northstar Wireless or Northstar Spectrum
Loss contingency terms
Percentage Of Bidding Credit					15.00%
Bidding Credit		$ 1,961,000,000
Northstar Wireless or Northstar Spectrum | AWS-3 Licenses [Member]
Loss contingency terms
Percentage Of Bidding Credit	25.00%				25.00%
Northstar Wireless or Northstar Spectrum | AWS-3 Licenses [Member] | Vermont National Telephone Company [Member]
Loss contingency terms
Bidding Credit	$ 3,300,000,000
Northstar Wireless or Northstar Spectrum | AWS-3 Licenses [Member] | Minimum | Vermont National Telephone Company [Member]
Loss contingencies
Claim amount	5,500
Northstar Wireless or Northstar Spectrum | AWS-3 Licenses [Member] | Maximum | Vermont National Telephone Company [Member]
Loss contingencies
Claim amount	$ 11,000
Lightsquared Harbinger Capital Partners LLC
Loss contingency terms
Business days allowed to terminate existing agreements					3 days
LightSquared transaction shareholder derivative actions
Loss contingencies
Number of shareholders who filed lawsuits | item					5
Do Not Call Litigation
Loss contingencies
Period of injunctive relief sought from placing any outbound telemarketing calls to market or promote its goods or services					5 years
Do Not Call Litigation | OHIO
Loss contingencies
Claim amount					$ 10,000,000
Do Not Call Litigation | CALIFORNIA
Loss contingencies
Claim amount from state plaintiff					100,000,000
Do Not Call Litigation | Illinois And North Carolina [Member]
Loss contingencies
Claim Amount Minimum That Would Not Raise Constitutional Concerns					1,000,000,000
Do Not Call Litigation | DISH Network L.L.C.
Loss contingencies
Claim amount			$ 270,000,000
Claim amount from state plaintiff					23,500,000,000
Do Not Call Litigation | Maximum | DISH Network L.L.C.
Loss contingencies
Claim amount from federal plaintiff					$ 900,000,000
Krakauer Action [Member]
Loss contingencies
Third Party Number Of Calls Made In Case | item							51,119
Third Party Number Of Calls Made In Case Damages Per Call | $ / item							400