DEBT - Credit Facilities Narrative (Details) - USD ($)	1 Months Ended		9 Months Ended
	Jul. 31, 2018	Jan. 31, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Line of Credit Facility [Line Items]
Proceeds from credit facility debt, net of discounts			$ 2,217,500,000	$ 5,602,425,000
Principal Amount			6,282,938,000		$ 4,693,675,000
Repayment of credit facility debt			635,738,000	3,684,668,000
Repayments of Senior Debt			2,623,756,000	$ 1,729,400,000
CSC Holdings Revolving Credit Facility | Revolving Credit Facility
Line of Credit Facility [Line Items]
Proceeds from credit facility debt, net of discounts	$ 575,000,000	$ 150,000,000
Principal Amount			575,000,000		450,000,000
Repayment of credit facility debt		600,000,000
CSC Holdings Term Loan Facility | Term Loan
Line of Credit Facility [Line Items]
Principal Amount		$ 1,500,000,000	2,962,500,000		2,985,000,000
Debt issued percentage of par		99.50%
CSC Holdings Term Loan Facility | Term Loan | Base Rate
Line of Credit Facility [Line Items]
basis spread on variable rate		1.50%
CSC Holdings Term Loan Facility | Term Loan | Eurodollar
Line of Credit Facility [Line Items]
basis spread on variable rate		2.50%
Senior Notes
Line of Credit Facility [Line Items]
Principal Amount			15,739,245,000		16,289,245,000
Senior Notes | CSC Holdings 7.625% Notes due July 15, 2018 [Member]
Line of Credit Facility [Line Items]
Principal Amount			$ 0		$ 500,000,000
Repayments of Senior Debt	$ 500,000,000