DESCRIPTION OF BUSINESS, RELATED MATTERS AND BASIS OF PRESENTATION (Details)			1 Months Ended		12 Months Ended
		Sep. 16, 2015 USD ($) $ / shares	Oct. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) Segment $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($)	Jul. 01, 2013 USD ($)
The Company and Related Matters [Abstract]
Number of reportable business segments | Segment					3
Termination fee to be paid by Cablevision		$ 280,000,000
Termination fee to be paid by Altice		$ 560,000,000
Payments for merger related costs					$ 17,862,000
Investment Banking, Advisory, Brokerage, and Underwriting Fees and Commissions					32,500,000
Payments for repurchase of redeemable noncontrolling interest					$ 8,300,000	$ 0	$ 0
Bresnan Cable
The Company and Related Matters [Abstract]
Cash selling price for sale of entity								$ 1,625,000,000
Net cash received from Bresnan Sale							675,000,000
Reduction for certain funded indebtedness							962,000,000
Pretax gain (loss) recognized in connection with sale							$ 408,000,000
Discontinued operation, amount of adjustment to prior period gain (loss) on disposal, before income tax						$ 5,848,000
CNYG Class A Common Stock
The Company and Related Matters [Abstract]
Common stock, par value (in dollars per share) | $ / shares					$ 0.01	$ 0.01
CNYG Class B Common Stock
The Company and Related Matters [Abstract]
Common stock, par value (in dollars per share) | $ / shares					$ 0.01	$ 0.01
Altice N.V.
The Company and Related Matters [Abstract]
Business acquisition, share price (in dollars per share) | $ / shares		$ 34.90
Newsday Holdings LLC | Reportable Legal Entities
The Company and Related Matters [Abstract]
Payments for repurchase of redeemable noncontrolling interest				$ 8,300,000
Neptune Finco Corp. | Senior Secured Credit Facilities | Senior Secured Credit Facility
The Company and Related Matters [Abstract]
Issue amount			$ 3,800,000,000
Debt instrument, periodic payment, principal (percent)			0.25%
Neptune Finco Corp. | Senior Notes 10.125% Due 2023 | Senior Notes
The Company and Related Matters [Abstract]
Issue amount			$ 1,800,000,000
Interest rate (percent)			10.125%
Neptune Finco Corp. | Senior Notes 10.875% Due 2025 | Senior Notes
The Company and Related Matters [Abstract]
Issue amount			$ 2,000,000,000
Interest rate (percent)			10.875%
Neptune Finco Corp. | Senior Guaranteed 6.625% Notes Due 2025 | Senior Notes
The Company and Related Matters [Abstract]
Issue amount			$ 1,000,000,000
Interest rate (percent)			6.625%
Neptune Finco Corp. | Revolving Loan Facility | Senior Secured Credit Facilities | Senior Secured Credit Facility
The Company and Related Matters [Abstract]
Maximum credit borrowing capacity			$ 2,000,000,000
Debt instrument, covenant, leverage ratio			5.0
Letters of credit issued			$ 15,000,000
Cablevision Systems Corporation
Principles of Consolidation [Abstract]
Senior notes, principal outstanding					$ 2,799,024,000
Senior notes due to Newsday					$ 611,455,000
Cablevision Systems Corporation Employee Stock Plan | Stock Options
The Company and Related Matters [Abstract]
Stock options outstanding (in shares) | shares					13,353,217
Cablevision Systems Corporation Employee Stock Plan | Restricted and Performance Restricted Shares
The Company and Related Matters [Abstract]
Equity instrument other than options, nonvested (shares) | shares					6,847,848
Cablevision Systems Corporation Employee Stock Plan | Restricted Stock
The Company and Related Matters [Abstract]
Equity instrument other than options, nonvested (shares) | shares					4,967,748	5,314,870
Cablevision Systems Corporation Employee Stock Plan | Performance Shares
The Company and Related Matters [Abstract]
Equity instrument other than options, nonvested (shares) | shares	[1]				1,772,430	0
Cablevision Systems Corporation Stock Plan for Non-Employee Directors | Restricted Stock
The Company and Related Matters [Abstract]
Non-option equity instruments, outstanding (shares) | shares					466,283

[1] The PSUs entitle the employee to shares of CNYG common stock up to 150% of the number of PSUs granted depending on the level of achievement of the specified performance criteria. If the minimum performance threshold is not met, no shares will be issued. Accrued dividends are paid to the extent that a PSU vests and the related stock is issued.