DEBT - Senior Guaranteed Notes, Senior Secured Notes, and Senior Notes and Debentures (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Debt Instrument [Line Items]
Principal amount	$ (26,499,564,000)		$ (26,499,564,000)		$ (24,773,440,000)
Long-term debt	26,185,687,000		26,185,687,000		24,420,285,000
Loss on extinguishment of debt and write-off of deferred financing costs	0	$ 1,194,000	0	$ 159,096,000
Stock Issued During Period, Value, New Issues		$ 244,000
Collateralized Agreements	37,581,000		37,581,000
Long-term Debt, Current Maturities	(1,859,290,000)		(1,859,290,000)		(170,682,000)
Notes Payable that will be reclassed to collateralized debt upon maturity	59,451,000		59,451,000
Senior guaranteed notes
Debt Instrument [Line Items]
Principal amount	(1,095,825,000)		(1,095,825,000)		0
Long-term Debt, Current Maturities	(1,083,676,000)		(1,083,676,000)		0
CSC Holdings Senior Notes
Debt Instrument [Line Items]
Principal amount	(619,621,000)		(619,621,000)		0
Long-term Debt, Current Maturities	(608,177,000)		(608,177,000)		0
CSC Holdings Revolving Credit Facility, Portion Due October 9, 2020 | Revolving Credit Facility
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	200,000		200,000
Senior Notes | CSC Holdings 5.750% Notes due January 15, 2030
Debt Instrument [Line Items]
Principal amount	$ (2,250,000,000)		$ (2,250,000,000)		(2,250,000,000)
Stated interest rate	5.75%		5.75%
Outstanding debt	$ 2,287,660,000		$ 2,287,660,000		2,289,168,000
Secured Debt [Member] | 5.5% Notes due April 15, 2027
Debt Instrument [Line Items]
Principal amount	$ (1,310,000,000)		$ (1,310,000,000)		(1,310,000,000)
Stated interest rate	5.50%		5.50%
Outstanding debt	$ 1,305,688,000		$ 1,305,688,000		1,305,430,000
Long-term Debt
Debt Instrument [Line Items]
Principal amount	$ (24,616,681,000)		$ (24,616,681,000)		$ (24,602,758,000)