Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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DEBT - CSC Holdings Credit Facilities (Details) - USD ($)	1 Months Ended	3 Months Ended						9 Months Ended
	Sep. 30, 2020	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Principal amount		$ 26,917,870,000						$ 26,917,870,000		$ 26,940,911,000
Loss on extinguishment of debt and write-off of deferred financing costs		0			$ 250,489,000			51,712,000	$ 250,489,000
Proceeds from long-term debt								3,310,000,000	6,197,046,000
Repayments of line of credit								3,483,026,000	5,374,522,000
Loss on extinguishment of debt and write-off of deferred financing costs		0			(250,489,000)			(51,712,000)	(250,489,000)
CSC Holdings
Debt Instrument [Line Items]
Loss on extinguishment of debt and write-off of deferred financing costs		0			250,489,000			51,712,000	250,489,000
Cash distributions to parent		77,957,000	$ 184,478,000	$ 501,000,000	431,100,000	$ 652,383,000	$ 720,350,000	763,435,000	1,803,833,000
Proceeds from long-term debt								3,310,000,000	6,197,046,000
Repayments of line of credit								3,483,026,000	5,374,522,000
Loss on extinguishment of debt and write-off of deferred financing costs		0			$ (250,489,000)			(51,712,000)	$ (250,489,000)
5.5% Notes due April 15, 2027 \| Secured Debt [Member]
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%
8.0% Notes due April 15, 2020 \| Senior Notes
Debt Instrument [Line Items]
Principal amount		$ 1,000,000,000						$ 1,000,000,000		1,000,000,000
Stated interest rate		3.375%						3.375%
Secured Debt [Member] \| CSC Holdings Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate								2.25%
Secured Debt [Member] \| Incremental Term Loan B-3
Debt Instrument [Line Items]
Principal amount		$ 1,243,125,000						$ 1,243,125,000		1,252,688,000
Secured Debt [Member] \| Incremental Term Loan B-5
Debt Instrument [Line Items]
Principal amount		2,955,000,000						$ 2,955,000,000		2,977,500,000
Secured Debt [Member] \| CSC Holdings Revolving Credit Facility - Non-Extend Creditors [Member] \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate								3.25%
Secured Debt [Member] \| Cablevision Lightpath Term B Loan
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		100,000,000						$ 100,000,000
Principal amount		595,500,000						595,500,000		600,000,000
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 \| Eurodollar
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		2,475,000,000						2,475,000,000
Principal amount		$ 150,000,000						$ 150,000,000		$ 625,000,000