EQUITY - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders equity balance	$ 503	$ 618	$ 437	$ 624
Net income	125	25
Noncontrolling Interests
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders equity balance	861	808	854	$ 806
Net income	32	37
Noncontrolling Interests | Hospital Operations
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders equity balance	116		114
Net income	2	2
Noncontrolling Interests | Ambulatory Care
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders equity balance	745		$ 740
Net income	$ 30	$ 35