DEBT - Credit Silo Combination (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Principal amount	$ 24,822,804	$ 24,817,366
Long-term debt	24,447,335	24,420,285
Face Amount of Senior Notes and Senior Guaranteed Notes	15,657,497	15,657,497
Carrying amount of Senior Notes and Senior Guaranteed Notes	15,488,589	15,476,496
Face amount of Credit Facility Debt	7,179,750	7,190,438
Carrying value of Credit Facility Debt	7,139,133	7,148,287
Finance Lease, Liability	91,394	69,420
Long-term Debt, Current Maturities	179,515	170,682
Finance Lease, Liability, Current	30,845	22,017
Long-term Debt, Excluding Current Maturities	24,267,820	24,249,603
Principal Amount	24,822,804	24,817,366
Loans Payable
Debt Instrument [Line Items]
Principal amount	75,920	83,415
Long-term debt	75,920	83,415
Principal Amount	75,920	83,415
Credit Facility [Domain]
Debt Instrument [Line Items]
Principal amount	72,750	65,250
Long-term Debt, Current Maturities	72,750	65,250
Principal Amount	72,750	65,250
Short-term Debt
Debt Instrument [Line Items]
Principal amount	179,515	170,682
Long-term Debt, Current Maturities	179,515	170,682
Principal Amount	179,515	170,682
Incremental Term Loan B-3 \| Secured Debt [Member]
Debt Instrument [Line Items]
Principal amount	$ 1,262,250	1,265,438
Stated interest rate	2.86%
Credit facility	$ 1,257,221	1,260,200
Principal Amount	1,262,250	1,265,438
CSC Holdings Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Principal amount	0	0
Line of Credit Facility, Maximum Borrowing Capacity	2,275,000
Credit facility	0	0
Principal Amount	$ 0	0
CSC Holdings Revolving Credit Facility \| Secured Debt [Member] \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
CSC Holdings Term Loan B \| Secured Debt [Member]
Debt Instrument [Line Items]
Principal amount	$ 2,917,500	2,925,000
Stated interest rate	2.86%
Credit facility	$ 2,904,808	2,911,729
Principal Amount	2,917,500	2,925,000
Incremental Term Loan B-5 \| Secured Debt [Member]
Debt Instrument [Line Items]
Principal amount	$ 3,000,000	3,000,000
Stated interest rate	3.11%
Credit facility	$ 2,977,104	2,976,358
Principal Amount	3,000,000	3,000,000
Secured Debt [Member]
Debt Instrument [Line Items]
Principal amount	1,759,017	1,759,017
Long-term debt	1,593,073	1,585,088
Principal Amount	1,759,017	1,759,017
Loans Payable
Debt Instrument [Line Items]
Principal amount	135,146	140,994
Long-term debt	135,146	140,994
Principal Amount	135,146	140,994
Senior Notes \| 6.75% Notes due November 15, 2021
Debt Instrument [Line Items]
Principal amount	$ 1,000,000	1,000,000
Stated interest rate	6.75%
Outstanding debt	$ 981,769	979,178
Principal Amount	1,000,000	1,000,000
Senior Notes \| 5.875% Notes due September 15, 2022
Debt Instrument [Line Items]
Principal amount	$ 649,024	649,024
Stated interest rate	5.875%
Outstanding debt	$ 604,810	600,849
Principal Amount	649,024	649,024
Senior Notes \| 5.25% Notes due June 1, 2024
Debt Instrument [Line Items]
Principal amount	$ 750,000	750,000
Stated interest rate	5.25%
Outstanding debt	$ 687,105	683,940
Principal Amount	750,000	750,000
Senior Notes \| Cablevision 7.750% Notes due July 15, 2025
Debt Instrument [Line Items]
Principal amount	$ 1,740	1,740
Stated interest rate	7.75%
Outstanding debt	$ 1,698	1,695
Principal Amount	1,740	1,740
Senior Notes \| 10.875% Notes due October 15, 2025
Debt Instrument [Line Items]
Principal amount	$ 1,684,221	1,684,221
Stated interest rate	10.875%
Outstanding debt	$ 1,665,828	1,665,237
Principal Amount	1,684,221	1,684,221
Senior Notes \| Cablevision 7.500% Notes due April 1, 2028
Debt Instrument [Line Items]
Principal amount	$ 4,118	4,118
Stated interest rate	7.50%
Outstanding debt	$ 4,112	4,112
Principal Amount	4,118	4,118
Senior Notes \| CSC Holdings 7.750% Notes due July 15, 2025
Debt Instrument [Line Items]
Principal amount	$ 617,881	617,881
Stated interest rate	7.75%
Outstanding debt	$ 606,026	605,583
Principal Amount	617,881	617,881
Senior Notes \| CSC Holdings 7.500% Notes due April 1, 2028
Debt Instrument [Line Items]
Principal amount	$ 1,045,882	1,045,882
Stated interest rate	7.50%
Outstanding debt	$ 1,044,313	1,044,278
Principal Amount	1,045,882	1,045,882
Senior Notes \| CSC Holdings 5.750% Notes due January 15, 2030
Debt Instrument [Line Items]
Principal amount	$ 2,250,000	2,250,000
Stated interest rate	5.75%
Outstanding debt	$ 2,288,419	2,289,168
Principal Amount	2,250,000	2,250,000
Secured Debt [Member] \| CSC Holdings 5.375% Senior Guaranteed Notes due July 15, 2023
Debt Instrument [Line Items]
Principal amount	$ 1,095,825	1,095,825
Stated interest rate	5.375%
Outstanding debt	$ 1,082,771	1,081,879
Principal Amount	1,095,825	1,095,825
Secured Debt [Member] \| CSC Holdings 5.500% Notes due May 15, 2026
Debt Instrument [Line Items]
Principal amount	$ 1,498,806	1,498,806
Stated interest rate	5.50%
Outstanding debt	$ 1,486,333	1,485,911
Principal Amount	1,498,806	1,498,806
Secured Debt [Member] \| 6.625% Notes due October 15, 2025
Debt Instrument [Line Items]
Principal amount	$ 1,000,000	1,000,000
Stated interest rate	6.625%
Outstanding debt	$ 989,855	989,483
Principal Amount	1,000,000	1,000,000
Secured Debt [Member] \| 5.5% Notes due April 15, 2027
Debt Instrument [Line Items]
Principal amount	$ 1,310,000	1,310,000
Stated interest rate	5.50%
Outstanding debt	$ 1,305,558	1,305,430
Principal Amount	1,310,000	1,310,000
Secured Debt [Member] \| 5.375% Senior Guaranteed Notes Due February 1, 2028
Debt Instrument [Line Items]
Principal amount	$ 1,000,000	1,000,000
Stated interest rate	5.375%
Outstanding debt	$ 992,935	992,757
Principal Amount	1,000,000	1,000,000
Secured Debt [Member] \| CSC Holdings 6.500% Notes due February 1, 2029
Debt Instrument [Line Items]
Principal amount	$ 1,750,000	1,750,000
Stated interest rate	6.50%
Outstanding debt	$ 1,747,057	1,746,996
Principal Amount	1,750,000	1,750,000
Long-term Debt
Debt Instrument [Line Items]
Principal amount	24,643,289	24,646,684
Long-term Debt, Excluding Current Maturities	24,267,820	24,249,603
Principal Amount	$ 24,643,289	$ 24,646,684

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

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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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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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