Funding Sources (Details) - USD ($)	1 Months Ended	3 Months Ended
	Apr. 30, 2016	Mar. 31, 2016	Oct. 31, 2016	Sep. 30, 2016	May 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Sale Leaseback Transaction, Net Book Value		$ 1,200,000,000		$ 502,000,000		$ 1,300,000,000
Sale Leaseback Transaction, Net Proceeds, Financing Activities		$ 600,000,000
Bridge Loan				0.0485
MLS 2nd Tranche [Member]
Financing Receivable, Recorded Investment [Line Items]
Sale Leaseback Transaction, Net Book Value				758,000,000	$ 1,300,000,000
Sale Leaseback Transaction, Net Proceeds, Investing Activities	$ 1,100,000,000
Network Sale-Leaseback [Member]
Financing Receivable, Recorded Investment [Line Items]
Sale Leaseback Transaction, Net Book Value	3,000,000,000			2,700,000,000
Sale Leaseback Transaction, Net Proceeds, Financing Activities	$ 2,200,000,000
Revolving Credit Facility [Member] | Unsecured Revolving Credit Facility expires in 2018 [Member]
Financing Receivable, Recorded Investment [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity				$ 3,000,000,000
Subsequent Event [Member] | Secured Debt [Member] | Spectrum Financing [Member]
Financing Receivable, Recorded Investment [Line Items]
Debt instrument face amount			$ 3,500,000,000