SEGMENT INFORMATION - Reconciling Items (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Assets:	$ 26,250		$ 26,250		$ 23,365
Capital expenditures:	106	$ 144	288	$ 336
Net operating revenues	3,648	4,560	8,168	9,105
Equity in earnings of unconsolidated affiliates:	31	42	59	76
Adjusted EBITDA	732	669	1,317	1,292
Depreciation and amortization:	206	214	409	422
Adjusted EBITDA and other reconciling items
Adjusted EBITDA	732	669	1,317	1,292
Loss from divested and closed businesses (i.e., the Company’s health plan businesses)	0	0	0	(1)
Depreciation and amortization	(206)	(214)	(409)	(422)
Impairment and restructuring charges, and acquisition-related costs	(54)	(36)	(109)	(55)
Litigation and investigation costs	(2)	(18)	(4)	(31)
Interest expense	(255)	(247)	(498)	(498)
Loss from early extinguishment of debt	(4)	0	(4)	(47)
Other non-operating income (expense), net	2	(1)	3	0
Net gains (losses) on sales, consolidation and deconsolidation of facilities	1	(1)	3	(2)
Income from continuing operations, before income taxes	214	152	299	236
Inter-segment eliminations
Segment Reporting Information [Line Items]
Net operating revenues	(113)	(146)	(249)	(292)
Hospital Operations
Segment Reporting Information [Line Items]
Assets:	18,807		18,807		16,196
Capital expenditures:	90	118	257	288
Equity in earnings of unconsolidated affiliates:	(4)	8	(2)	11
Adjusted EBITDA	492	359	834	706
Depreciation and amortization:	177	185	352	364
Adjusted EBITDA and other reconciling items
Adjusted EBITDA	492	359	834	706
Depreciation and amortization	(177)	(185)	(352)	(364)
Hospital Operations | Operating segments
Segment Reporting Information [Line Items]
Net operating revenues	3,088	3,827	6,922	7,689
Ambulatory Care
Segment Reporting Information [Line Items]
Assets:	6,470		6,470		6,195
Capital expenditures:	10	21	21	41
Net operating revenues	368	524	858	1,004
Equity in earnings of unconsolidated affiliates:	35	34	61	65
Adjusted EBITDA	167	207	323	384
Depreciation and amortization:	20	18	39	36
Adjusted EBITDA and other reconciling items
Adjusted EBITDA	167	207	323	384
Depreciation and amortization	(20)	(18)	(39)	(36)
Ambulatory Care | Operating segments
Segment Reporting Information [Line Items]
Net operating revenues	368	524	858	1,004
Conifer
Segment Reporting Information [Line Items]
Assets:	973		973		$ 974
Capital expenditures:	6	5	10	7
Net operating revenues	305	355	637	704
Adjusted EBITDA	73	103	160	202
Depreciation and amortization:	9	11	18	22
Adjusted EBITDA and other reconciling items
Adjusted EBITDA	73	103	160	202
Depreciation and amortization	(9)	(11)	(18)	(22)
Conifer | Operating segments
Segment Reporting Information [Line Items]
Net operating revenues	305	355	637	704
Conifer | Tenet | Operating segments
Segment Reporting Information [Line Items]
Net operating revenues	113	146	249	292
Conifer | Other clients | Operating segments
Segment Reporting Information [Line Items]
Net operating revenues	$ 192	$ 209	$ 388	$ 412