RESTRUCTURING COSTS AND OTHER EXPENSE (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Restructuring Reserve [Roll Forward]
Accrual, beginning balance			$ 123,100
Restructuring charges		$ 12,246	7,516	$ 88,997
Payments and other			(71,545)
Accrual, ending balance	$ 59,071		59,071
Transaction costs	3,496	$ 142	5,762	$ 320
Severance and Other Employee Related Costs
Restructuring Reserve [Roll Forward]
Accrual, beginning balance			113,474
Restructuring charges			4,182
Payments and other			(65,692)
Accrual, ending balance	51,964		51,964
Facility Realignment and Other Costs
Restructuring Reserve [Roll Forward]
Accrual, beginning balance			9,626
Restructuring charges			3,334
Payments and other			(5,853)
Accrual, ending balance	7,107		7,107
Cablevision
Restructuring Reserve [Roll Forward]
Cumulative restructuring costs	315,319		315,319
Cequel
Restructuring Reserve [Roll Forward]
Cumulative restructuring costs	$ 68,696		$ 68,696