DEBT - Senior Guaranteed Notes and Senior Notes and Debentures (Details) - USD ($)	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Debt Instrument [Line Items]
Principal amount	$ 26,544,747,000		$ 26,671,018,000
Less: Current portion	639,996,000		635,310,000
Face Amount of Senior Notes and Senior Guaranteed Notes	7,660,000,000		7,660,000,000
Carrying amount of Senior Notes and Senior Guaranteed Notes	7,636,312,000		7,635,633,000
Face amount of Credit Facility Debt	7,774,250,000		7,952,438,000
Carrying value of Credit Facility Debt	7,740,569,000		7,916,492,000
Finance Lease, Liability	237,082,000		218,735,000
Long-term debt	26,440,831,000		26,546,760,000
Debt	969,413,000		917,313,000
Finance Lease, Liability, Current	121,201,000		109,204,000
Long-term debt, net of current maturities	25,471,418,000		25,629,447,000
Repayments of line of credit	329,688,000	$ 225,863,000
Loans Payable
Debt Instrument [Line Items]
Principal amount			94,049,000
Long-term debt	129,466,000		94,049,000
Short-term Debt
Debt Instrument [Line Items]
Principal amount	978,441,000		931,027,000
Debt	969,413,000		917,313,000
Credit Facility [Domain]
Debt Instrument [Line Items]
Principal amount			78,750,000
Debt	78,750,000		78,750,000
Incremental Term Loan B-3 \| Secured Debt [Member]
Debt Instrument [Line Items]
Principal amount	$ 1,236,750,000		1,239,938,000
Stated interest rate	2.647%
Credit facility	$ 1,233,418,000		1,236,394,000
Incremental Term Loan B-5 \| Secured Debt [Member]
Debt Instrument [Line Items]
Principal amount	$ 2,940,000,000		2,947,500,000
Stated interest rate	2.897%
Credit facility	$ 2,923,069,000		2,929,813,000
Loans Payable
Debt Instrument [Line Items]
Principal amount	132,874,000		97,804,000
Long-term debt	132,874,000		97,804,000
Secured Debt [Member]
Debt Instrument [Line Items]
Principal amount	1,759,017,000		1,759,017,000
Long-term debt	1,716,600,000		1,706,997,000
CSC Holdings Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Principal amount	$ 740,000,000		900,000,000
Stated interest rate	2.647%
Line of Credit Facility, Maximum Borrowing Capacity	$ 2,475,000,000
Credit facility	$ 734,574,000		893,864,000
Secured Debt [Member] \| 5.5% Notes due April 15, 2027
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.50%
Principal amount	$ 1,310,000,000		1,310,000,000
Carrying Amount	$ 1,306,649,000		1,306,508,000
Secured Debt [Member] \| 5.375% Senior Guaranteed Notes Due February 1, 2028
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.375%
Principal amount	$ 1,000,000,000		1,000,000,000
Carrying Amount	$ 994,459,000		994,262,000
Secured Debt [Member] \| CSC Holdings 6.500% Notes due February 1, 2029
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.50%
Principal amount	$ 1,750,000,000		1,750,000,000
Carrying Amount	1,747,579,000		1,747,511,000
Long-term Debt
Debt Instrument [Line Items]
Principal amount	25,566,306,000		25,739,991,000
Long-term debt, net of current maturities	$ 25,471,418,000		25,629,447,000
Senior Notes \| 5.25% Notes due June 1, 2024
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.25%
Principal amount	$ 750,000,000		750,000,000
Carrying Amount	$ 714,781,000		711,137,000
Senior Notes \| CSC Holdings 7.500% Notes due April 1, 2028
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.50%
Principal amount	$ 1,045,882,000		1,045,882,000
Carrying Amount	$ 1,044,622,000		1,044,582,000
Senior Notes \| 8.0% Notes due April 15, 2020
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.375%
Principal amount	$ 1,000,000,000		1,000,000,000
Carrying Amount	$ 997,040,000		996,970,000
Senior Notes \| 5.875% Notes due September 15, 2022
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.875%
Principal amount	$ 649,024,000		649,024,000
Carrying Amount	$ 639,996,000		635,310,000
Senior Notes \| Cablevision 7.500% Notes due April 1, 2028
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.50%
Principal amount	$ 4,118,000		4,118,000
Carrying Amount	$ 4,113,000		4,113,000
Senior Notes \| CSC Holdings 5.750% Notes due January 15, 2030
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.75%
Principal amount	$ 2,250,000,000		2,250,000,000
Carrying Amount	$ 2,282,054,000		$ 2,282,875,000

Carrying amount of Senior Notes and Senior Guaranteed Notes

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Carrying value of Credit Facility Debt

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Face amount of Credit Facility Debt

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Face Amount of Senior Notes and Senior Guaranteed Notes

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

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

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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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Present value of lessee's discounted obligation for lease payments from finance lease.

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The effective interest rate at the end of the reporting period.

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Carrying value as of the balance sheet date of the portion of long-term notes having the highest claim on the assets of the issuer in case of bankruptcy or liquidation, due within one year or the normal operating cycle, if longer. Senior note holders are paid off in full before any payments are made to debt holders having a lesser priority of repayment.

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