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DEBT - CSC Holdings Credit Facilities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Debt Instrument [Line Items]
Principal amount	$ 25,118,471		$ 25,126,605
Loss (gain) on extinguishment of debt and write-off of deferred financing costs	7,035	$ (4,393)
Proceeds from long-term debt	2,950,000	350,000
Repayments of line of credit	2,967,306	268,936
Gain (loss) on extinguishment of debt and write-off of deferred financing costs	(7,035)	4,393
CSC Holdings
Debt Instrument [Line Items]
Loss (gain) on extinguishment of debt and write-off of deferred financing costs	7,035	(4,393)
Dividends, Cash	3,775	83
Proceeds from long-term debt	2,950,000	350,000
Repayments of line of credit	2,967,306	268,936
Gain (loss) on extinguishment of debt and write-off of deferred financing costs	(7,035)	$ 4,393
CSC Holdings Term Loans B and B-3
Debt Instrument [Line Items]
Write-off of deferred financings costs	$ 2,598
Secured Debt [Member] \| Synthetic LIBOR Rate (one month)
Debt Instrument [Line Items]
Basis spread on variable rate	0.11448%
Secured Debt [Member] \| Synthetic LIBOR Rate (three months)
Debt Instrument [Line Items]
Basis spread on variable rate	0.26161%
Secured Debt [Member] \| Synthetic LIBOR Rate (six months)
Debt Instrument [Line Items]
Basis spread on variable rate	0.42826%
Secured Debt [Member] \| Cablevision Lightpath Term B Loan
Debt Instrument [Line Items]
Principal amount	$ 580,500		582,000
Secured Debt [Member] \| Cablevision Lightpath Term B Loan \| Alternate base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Secured Debt [Member] \| Cablevision Lightpath Term B Loan \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Basis spread on variable rate	3.25%
Revolving Credit Facility \| CSC Holdings Revolving Credit Facility
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 2,475
Principal amount	1,600,000		$ 825,000
Proceeds from long-term debt	900
Repayments of line of credit	$ 125