Additional Financial Information (Details) (USD $) In Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Jul. 31, 2011	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Other Current Assets [Abstract]
Prepaid income taxes		$ 0		$ 0		$ 287
Other prepaid expenses		144		144		115
Other current assets		26		26		23
Total other current assets		170		170		425
Other Current Liabilities [Abstract]
Accrued interest		520		520		507
Accrued compensation and benefits		291		291		357
Accrued insurance		158		158		152
Accrued franchise fees		150		150		166
Accrued sales and other taxes		68		68		92
Accrued rent		48		48		50
Accrued share repurchases		45		45		43
Other accrued expenses		296		296		262
Total other current liabilities		1,576		1,576		1,629
Revenues [Abstract]
Residential services revenues		4,300	4,195	8,559	8,309
Business services revenues		361	268	673	522
Advertising revenues		225	216	422	389
Other revenues		58	55	117	113
Total revenues		4,944	4,734	9,771	9,333
Interest Income Expense Net [Abstract]
Interest income		1	0	3	0
Interest expense		(367)	(341)	(732)	(688)
Interest expense, net		(366)	(341)	(729)	(688)
Component Of Other Expense Nonoperating [Line Items]
Other expense, net		(32)	(18)	(62)	(33)
Related Party Transactions [Abstract]
Related party revenues		6	4	9	7
Related party costs of revenues		(64)	(78)	(128)	(138)
Supplemental Cash Flow Information [Abstract]
Cash paid for interest				(793)	(703)
Interest income received				73	34
Cash paid for interest, net				(720)	(669)
Cash paid for income taxes				(50)	(284)
Cash refunds of income taxes				271	90
Cash (paid for) refunds of income taxes, net				221	(194)
Payments for stock repurchased and retired	45			1,691	0
Loss From Equity Investments Net [Member]
Component Of Other Expense Nonoperating [Line Items]
Other expense, net		(32)	(21)	(57)	(41)
Gain (Loss) On Equity Award Reimbursement Obligation To Time Warner [Member]
Component Of Other Expense Nonoperating [Line Items]
Other expense, net		0	3	(5)	7
Other Income Net [Member]
Component Of Other Expense Nonoperating [Line Items]
Other expense, net		$ 0	$ 0	$ 0	$ 1