SEGMENT DATA Revenues (Details) - USD ($) $ in Thousands	3 Months Ended							12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting [Abstract]
Television advertising								$ 471,227	$ 435,096	$ 409,469
Carriage fees and subscriptions								83,232	71,331	66,644
Other								19,753	19,747	20,082
Total net revenues	$ 196,154	$ 119,431	$ 146,895	$ 111,732	$ 107,527	$ 142,803	$ 105,817	$ 574,212	$ 526,174	$ 496,195