ACQUISITIONS - Preliminary purchase price allocations (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Final purchase price allocations
Goodwill	$ 7,308		$ 7,252
Series of individual business acquisitions
Final purchase price allocations
Current assets	6	$ 2
Property and equipment	8	5
Other intangible assets	8	1
Goodwill	83	3
Other long-term assets, including previously held equity method investments	5
Other long-term assets, including previously held equity method investments		(1)
Current liabilities	(8)	0
Long-term liabilities	(6)	(1)
Redeemable noncontrolling interests in equity of consolidated subsidiaries	(30)	(1)
Noncontrolling interests	(11)	(1)
Cash paid, net of cash acquired	(55)	(2)
Gains on consolidations	$ 0	$ 5