ACQUISITIONS AND DISPOSITIONS OF ASSETS - Acquired Operations Included in the Financial Statements (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Acquisitions
Revenue	$ 1,512	$ 1,539	$ 1,283	$ 1,609	$ 1,622	$ 1,125	$ 771	$ 722	$ 5,943	$ 4,240	$ 3,055
Operating (loss) income	$ 625	$ (4,216)	$ 492	$ 327	$ 277	$ (6)	$ 106	$ 93	(2,772)	470	660
Selling, general, and administrative expenses									832	732	$ 630
RSN
Acquisitions
Revenue									2,562	1,139
Operating (loss) income									(3,585)	70
Selling, general, and administrative expenses									98	35
Other Acquisitions In 2020
Acquisitions
Revenue									3	0
Operating (loss) income									(2)	0
Total Acquisitions
Acquisitions
Revenue									2,565	1,139
Operating (loss) income									$ (3,587)	$ 70