Commitments and Contingencies - (Details)					1 Months Ended		3 Months Ended			9 Months Ended		24 Months Ended	117 Months Ended
	Jun. 05, 2017 USD ($)	Oct. 03, 2016	Feb. 12, 2015 USD ($)	Dec. 23, 2013 USD ($)	Sep. 23, 2016 USD ($)	Jul. 31, 2009 item	Sep. 30, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2017 USD ($)
Spectrum Investments
Payment to acquire interest in non-controlling investments in certain entities													$ 11,000,000,000
Total investment										$ 90,381,000			21,000,000,000
Aggregate amount to the federal and state plaintiffs	$ 280,000,000
Term barred from conducting any outbound telemarketing	2 years
Term barred from accepting orders from independent third-party retailer	2 years
Litigation expense							$ 41,000,000
Litigation expense (Note 8 )								$ 20,000,000		295,695,000		$ 25,000,000
Dividend paid to DOC			$ 8,250,000,000						$ 1,500,000,000		$ 1,500,000,000
Claim amount	$ 280,000,000
Other accrued expenses
Spectrum Investments
Litigation Reserve							280,000,000			280,000,000			280,000,000
Loss Contingency Accrual							61,000,000			61,000,000			61,000,000
Vermont National Telephone Company | Maximum
Spectrum Investments
Aggregate amount to the federal and state plaintiffs					$ 11,000
Claim amount					11,000
Vermont National Telephone Company | Minimum
Spectrum Investments
Aggregate amount to the federal and state plaintiffs					5,500
Claim amount					5,500
Northstar Wireless or Northstar Spectrum | Vermont National Telephone Company
Spectrum Investments
Bidding credit value					$ 3,300,000,000
Northstar Wireless or Northstar Spectrum | American III
Spectrum Investments
Non-controlling investments							10,000,000,000			10,000,000,000			10,000,000,000
FTC Action
Spectrum Investments
Litigation expense							255,000,000
Satellite transponder guarantees
Spectrum Investments
Guarantor Obligations, Maximum Exposure, Undiscounted							$ 143,000,000			$ 143,000,000			$ 143,000,000
Technology Development Licensing
Spectrum Investments
Number of reexamination petitions pending before patent and trademark office | item						2
Telemarketing Litigation [Member]
Spectrum Investments
Period of injunctive relief sought from placing any outbound telemarketing calls to market or promote its goods or services		5 years								5 years
Telemarketing Litigation [Member] | DISH Network L.L.C.
Spectrum Investments
Aggregate amount to the federal and state plaintiffs				$ 270,000,000
Claim amount				$ 270,000,000
Claim amount from state plaintiff										$ 23,500,000,000
Telemarketing Litigation [Member] | Maximum | DISH Network L.L.C.
Spectrum Investments
Claim amount from federal plaintiff										$ 900,000,000
Lightsquared Harbinger Capital Partners LLC
Spectrum Investments
Business days allowed to terminate existing agreements										3 days
CALIFORNIA | Telemarketing Litigation [Member]
Spectrum Investments
Claim amount from state plaintiff										$ 100,000,000
OHIO | Telemarketing Litigation [Member]
Spectrum Investments
Claim amount from state plaintiff										10,000,000
Illinois And North Carolina [Member] | Telemarketing Litigation [Member]
Spectrum Investments
Claim Amount Minimum That Would Not Raise Constitutional Concerns										$ 1,000,000,000