Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings (Loss) Per Share [Abstract]
Antidilutive securities excluded from computation of earnings per share (in shares)	30,000,000	35,000,000	31,000,000	37,000,000
Net income attributable to Charter shareholders	$ 493	$ 48	$ 934	$ 342
Weighted average common shares outstanding, basic (shares)	230,554,633	253,923,805	234,159,830	262,074,603
Effect of assumed exercise or issuance of shares relating to stock plans on denominator (shares)	3,052,781	4,418,046	3,184,094	4,288,999
Weighted average common shares outstanding, diluted (shares)	233,607,414	258,341,851	237,343,924	266,363,602
Basic earnings per common share attributable to Charter shareholders (dollars per share)	$ 2.14	$ 0.19	$ 3.99	$ 1.31
Diluted earnings per common share attributable to Charter shareholders (dollars per share)	$ 2.11	$ 0.19	$ 3.93	$ 1.29