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AFFILIATE AND RELATED PARTY TRANSACTIONS - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 30, 2018	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jul. 06, 2016
Related Party Transaction [Line Items]
Equity in net income (loss) from investment in related party				$ 0	$ (10,849)	$ (10,040)
Related party expense				15,961	21,444	640,344
Cash distributions to shareholders		$ 839,700			1,499,935	840,035	$ 445,176
Cash distributions			$ 79,617	$ 0	1,499,935	919,317	$ 365,559
Fees for Executive Services \| Affiliates
Related Party Transaction [Line Items]
Related party expense					13,250
Equipment Purchase Costs \| Altice Management International
Related Party Transaction [Line Items]
Capital expenditures						22,012
I24News
Related Party Transaction [Line Items]
Equity in net income (loss) from investment in related party	$ 13,298				(1,130)	(2,821)
Ownership percentage	24.00%
Newsday
Related Party Transaction [Line Items]
Equity in net income (loss) from investment in related party					$ 9,719	7,219
Ownership percentage								25.00%
Altice N.V.
Related Party Transaction [Line Items]
Management advisory and consulting fee						$ 30,000