INTANGIBLE ASSETS - Summary of Acquired Indefinite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Acquired Indefinite-lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 208,172	$ 426,419	$ 666,041	$ 981,657
Cable television franchises	13,020,081		13,020,081		$ 13,020,081
Goodwill	8,012,416		8,012,416		8,019,861
Total	21,032,497		21,032,497		21,039,942
Cablevision
Acquired Indefinite-lived Intangible Assets [Line Items]
Cable television franchises	8,113,575		8,113,575		8,113,575
Goodwill	5,873,716		5,873,716		5,866,120
Total	13,987,291		13,987,291		13,979,695
Cequel
Acquired Indefinite-lived Intangible Assets [Line Items]
Cable television franchises	4,906,506		4,906,506		4,906,506
Goodwill	2,138,700		2,138,700		2,153,741
Total	$ 7,045,206		$ 7,045,206		$ 7,060,247