SEGMENT DATA - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) regional_sport_network segment market	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Segment data
Number of reportable segments | segment	2
Number of markets | market	89
Intersegment revenues	$ 35
Intersegment selling, general, and administrative expenses	35
Intersegment interest expense	$ 13	$ 15	$ 19
Operating segments | Sports
Segment data
Number of regional sports network brands | regional_sport_network	23