Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings (Loss) Per Share [Abstract]
Antidilutive securities excluded from computation of earnings per share (in shares)	31,000,000	37,000,000	31,000,000	37,000,000
Net income attributable to Charter shareholders	$ 273	$ 139	$ 441	$ 294
Weighted average common shares outstanding, basic (shares)	234,241,769	263,460,911	235,992,306	266,217,549
Effect of assumed exercise or issuance of shares relating to stock plans on denominator (shares)	2,831,797	3,848,350	3,254,421	4,031,884
Weighted average common shares outstanding, diluted (shares)	237,073,566	267,309,261	239,246,727	270,249,433
Basic earnings per common share attributable to Charter shareholders (dollars per share)	$ 1.17	$ 0.53	$ 1.87	$ 1.11
Diluted earnings per common share attributable to Charter shareholders (dollars per share)	$ 1.15	$ 0.52	$ 1.84	$ 1.09