DEBT - Credit Facilities Outstanding (Details) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term debt	$ 26,185,687,000	$ 24,420,285,000
Principal Amount	26,499,564,000	24,773,440,000
CSC Holdings Revolving Credit Facility, Portion Due October 9, 2020 \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	200,000
CSC Holdings Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	2,275,000,000
Credit facility, Carrying Value	0	0
Letters of credit outstanding	141,949,000
Line of credit facility, remaining borrowing capacity	2,333,051,000
Principal Amount	$ 0	0
CSC Holdings Term Loan B \| Secured Debt [Member]
Debt Instrument [Line Items]
Stated interest rate	2.435%
Credit facility, Carrying Value	$ 2,897,887,000	2,911,729,000
Principal Amount	$ 2,910,000,000	2,925,000,000
Incremental Term Loan B-3 \| Secured Debt [Member]
Debt Instrument [Line Items]
Stated interest rate	2.435%
Credit facility, Carrying Value	$ 1,254,243,000	1,260,200,000
Principal Amount	1,259,063,000	1,265,438,000
Secured Debt [Member]
Debt Instrument [Line Items]
Long-term debt	1,601,107,000	1,585,088,000
Principal Amount	$ 1,699,566,000	$ 1,699,566,000

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

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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- Definition

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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- Definition

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

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- Definition

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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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

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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