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DEBT - Narrative (Details) - USD ($)	3 Months Ended
DEBT - Narrative (Details) - USD ($)	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Debt Instrument [Line Items]
Proceeds from long-term debt	$ 450,000,000	$ 2,950,000,000
Repayments of line of credit	220,014,000	$ 2,967,306,000
Principal Amount	25,334,575,000		$ 25,096,412,000
2027 Revolving Credit Commitments
Debt Instrument [Line Items]
Line of credit facility, periodic payment amount	95,000
2025 Revolving Credit Commitments
Debt Instrument [Line Items]
Line of credit facility, periodic payment amount	20,000
CSC Holdings 11.7400% Senior Guaranteed Notes due Jan 31, 2029 \| Secured Debt [Member]
Debt Instrument [Line Items]
Principal Amount	$ 2,050,000,000
Stated interest rate	11.75%
Revolving Credit Facility \| CSC Holdings Revolving Credit Facility
Debt Instrument [Line Items]
Proceeds from long-term debt	$ 450,000
Repayments of line of credit	150,000
Principal Amount	2,000,000,000		1,700,000,000
Line of Credit Facility, Maximum Borrowing Capacity	2,475,000
Letters of credit outstanding	163,613,000
Revolving Credit Facility \| Cablevision Lightpath Revolving Credit Facility
Debt Instrument [Line Items]
Principal Amount	$ 0		0
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	$ 674,240,000		$ 676,000,000
Debt Instrument, Issued, Principal	$ 676,000
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%
Secured Debt [Member] \| Cablevision Lightpath Term B Loan Refinancing Amendment \| Alternate base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%
Secured Debt [Member] \| Cablevision Lightpath Term B Loan Refinancing Amendment \| Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%
Cablevision Lightpath Revolving Credit Facility \| Cablevision Lightpath Revolving Credit Facility
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 115,000
Letters of credit outstanding	$ 150,000