NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Programming (Details)	12 Months Ended
	Dec. 31, 2018
Minimum
Programming
Contract period	1 year
Maximum
Programming
Contract period	7 years
Programming Contracts with One Year Period
Programming
Period of program contracts amortized on straight-line basis	1 year
Programming Contracts with Two Year Periods
Programming
Period of program contracts amortized on straight-line basis	2 years