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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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DEBT - Senior Guaranteed Notes, Senior Secured Notes, and Senior Notes and Debentures (Details) - USD ($)	1 Months Ended	3 Months Ended
	Sep. 30, 2020	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Debt Instrument [Line Items]
Principal amount		$ 26,544,747,000		$ 26,671,018,000
Long-term debt		26,440,831,000		26,546,760,000
Issuance of common shares pursuant to employee long term incentive plan		10,000	$ 2,044,000
Notes Payable that will be reclassed to collateralized debt upon maturity		$ 59,451,000
Cablevision Lightpath LLC \| Cablevision Lightpath LLC
Debt Instrument [Line Items]
Ownership percentage of noncontrolling interest		50.01%
Cablevision Lightpath Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Principal amount		$ 0		0
Cablevision Lightpath Term B Loan \| Secured Debt [Member]
Debt Instrument [Line Items]
Principal amount		592,500,000		594,000,000
Line of Credit Facility, Maximum Borrowing Capacity		100,000,000
Cablevision Lightpath Term B Loan \| Secured Debt [Member] \| Alternate Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Cablevision Lightpath Term B Loan \| Secured Debt [Member] \| Eurodollar
Debt Instrument [Line Items]
Basis spread on variable rate	3.25%
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
Stated interest rate		5.75%
Senior Notes \| CSC Holdings 4.500% Senior Guaranteed Notes due November 15, 2021
Debt Instrument [Line Items]
Principal amount		$ 1,500,000,000		1,500,000,000
Stated interest rate		4.50%
Senior Notes \| CSC Holdings 5.000% Notes due November 15, 2031
Debt Instrument [Line Items]
Principal amount		$ 500,000,000		500,000,000
Stated interest rate		5.00%
Secured Debt [Member] \| 5.5% Notes due April 15, 2027
Debt Instrument [Line Items]
Principal amount		$ 1,310,000,000		1,310,000,000
Stated interest rate		5.50%
Long-term Debt
Debt Instrument [Line Items]
Principal amount		$ 25,566,306,000		$ 25,739,991,000