BENEFIT PLANS, Plan Assumptions for Defined Benefit Plans (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cablevision Defined Benefit Plans [Member]
Weighted-average assumptions used to determine net periodic benefit cost [Abstract]
Discount rate (in hundredths)	4.24%	3.67%	4.32%
Rate of increase in future compensation levels (in hundredths)	3.50%	3.50%	3.50%
Weighted-average assumptions used to determine benefit obligations [Abstract]
Discount rate (in hundredths)	3.70%	4.56%
Rate of increase in future compensation levels (in hundredths)	3.50%	3.50%
Pension Plan
Weighted-average assumptions used to determine net periodic benefit cost [Abstract]
Expected rate of return on plan assets (Pension Plan only) (in hundredths)	4.53%	3.60%	3.76%