Recently Issued Accounting Standards Recently Issued Accounting Standards (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2015
Product Information [Line Items]
REVENUES	$ 10,854	$ 10,357	$ 21,511	$ 20,521
New Accounting Pronouncement, Effect of Adoption on Noncurrent Assets			120
New Accounting Pronouncement, Effect of Adoption on Accounts Payable and Accrued Liabilities			71
New Accounting Pronouncement, Effect of Adoption on Deferred Income Taxes			11
New Accounting Pronouncement, Effect of Adoption on Total Shareholders' Equity			38
Governmental imposed fees passed through to the customer	245	238	491	473
Customer prepayments - account payable and accrued liabilities	401		401
Upfront installation fees - account payable and accrued liabilities	85		85
Long-term deferred revenue liabilities - other long-term liabilities	34		34
Deferred enterprise commission costs - noncurrent asset	134		134
Deferred upfront MDU fees - noncurrent asset	254		254
Amortization expense of deferred upfront MDU fees	15		30
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification					$ 22,300
Residential Video Product Line [Member]
Product Information [Line Items]
REVENUES	4,363	4,119	8,655	8,193
Residential Internet Product Line [Member]
Product Information [Line Items]
REVENUES	3,770	3,512	7,477	6,909
Residential Voice Product Line [Member]
Product Information [Line Items]
REVENUES	531	650	1,087	1,344
Residential Product Line [Member]
Product Information [Line Items]
REVENUES	8,664	8,281	17,219	16,446
Commercial Small and Medium Business Product Line [Member]
Product Information [Line Items]
REVENUES	915	890	1,815	1,756
Commercial Enterprise Product Line [Member]
Product Information [Line Items]
REVENUES	627	588	1,249	1,167
Commercial Product Line [Member]
Product Information [Line Items]
REVENUES	1,542	1,478	3,064	2,923
Advertising sales [Member]
Product Information [Line Items]
REVENUES	427	381	783	718
Other services [Member]
Product Information [Line Items]
REVENUES	$ 221	$ 217	$ 445	$ 434