Commitments and Contingencies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Commitments and Contingencies [Line Items]
Programming	$ 2,678	$ 2,459	$ 2,146
Franchise fees and other franchise-related costs	212	208	190
Letters of credit, amount	$ 67
Minimum [Member]
Commitments and Contingencies [Line Items]
Programming fee term (in years)	3 years
Maximum [Member]
Commitments and Contingencies [Line Items]
Programming fee term (in years)	10 years
Operating Leases and Rentals [Member]
Commitments and Contingencies [Line Items]
Lease and rental costs charged to expense	$ 49	43	34
Utility Pole Rental Agreement [Member]
Commitments and Contingencies [Line Items]
Lease and rental costs charged to expense	$ 53	49	$ 49
Montana Department of Revenue [Member]
Commitments and Contingencies [Line Items]
Property Tax Assessment on Cable Companies (percentage)	3.00%
Property Tax Assessment on Phone Companies (percentage)	6.00%
Reduction in Bresnan acquisition liabilities		8
Reduction in expenses for post-acquisition settlements		$ 3