Tenet Healthcare (THC) 10-K 25 Feb 19 2018 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2018	Jan. 31, 2019	Jun. 29, 2018
Document and Entity Information
Entity Registrant Name	TENET HEALTHCARE CORPORATION
Entity Central Index Key	70,318
Document Type	10-K
Document Period End Date	Dec. 31, 2018
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 2.3
Entity Common Stock, Shares Outstanding (in shares)		102,667,337
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	FY
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 411	$ 611
Accounts receivable (less allowance for doubtful accounts of $898 at December 31, 2017)	2,595	2,616
Inventories of supplies, at cost	305	289
Income tax receivable	21	5
Assets held for sale	107	1,017
Other current assets	1,197	1,035
Total current assets	4,636	5,573
Investments and other assets	1,456	1,543
Deferred income taxes	312	455
Property and equipment, at cost, less accumulated depreciation and amortization ($5,221 at December 31, 2018 and $4,739 at December 31, 2017)	6,993	7,030
Goodwill	7,281	7,018
Other intangible assets, at cost, less accumulated amortization ($1,013 at December 31, 2018 and $883 at December 31, 2017)	1,731	1,766
Total assets	22,409	23,385
Current liabilities:
Current portion of long-term debt	182	146
Accounts payable	1,207	1,175
Accrued compensation and benefits	838	848
Professional and general liability reserves	216	200
Accrued interest payable	240	256
Liabilities held for sale	43	480
Other current liabilities	1,131	1,227
Total current liabilities	3,857	4,332
Long-term debt, net of current portion	14,644	14,791
Professional and general liability reserves	666	654
Defined benefit plan obligations	521	536
Deferred income taxes	36	36
Other long-term liabilities	578	631
Total liabilities	20,302	20,980
Commitments and contingencies
Redeemable noncontrolling interests in equity of consolidated subsidiaries	1,420	1,866
Shareholders’ equity:
Common stock, $0.05 par value; authorized 262,500,000 shares; 150,897,143 shares issued at December 31, 2018 and 149,384,952 shares issued at December 31, 2017	7	7
Additional paid-in capital	4,747	4,859
Accumulated other comprehensive loss	(223)	(204)
Accumulated deficit	(2,236)	(2,390)
Common stock in treasury, at cost, 48,359,705 shares at December 31, 2018 and 48,413,169 shares at December 31, 2017	(2,414)	(2,419)
Total shareholders’ deficit	(119)	(147)
Noncontrolling interests	806	686
Total equity	687	539
Total liabilities and equity	$ 22,409	$ 23,385

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts (in dollars)		$ 898
Property and equipment, accumulated depreciation and amortization (in dollars)	$ 5,221	4,739
Other intangible assets, accumulated amortization (in dollars)	$ 1,013	$ 883
Common stock, par value (in dollars per share)	$ 0.05	$ 0.05
Common stock, number of shares authorized	262,500,000	262,500,000
Common stock, number of shares issued	150,897,143	149,384,952
Common stock, number of shares held in treasury	48,359,705	48,413,169

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement [Abstract]
Net operating revenues before provision for doubtful accounts		$ 20,613	$ 21,070
Provision for doubtful accounts	$ 0	1,434	1,449
Net operating revenues	18,313	19,179	19,621
Equity in earnings of unconsolidated affiliates	150	144	131
Operating expenses:
Salaries, wages and benefits	8,634	9,274	9,328
Supplies	3,004	3,085	3,124
Other operating expenses, net	4,259	4,570	4,891
Electronic health record incentives	(3)	(9)	(32)
Depreciation and amortization	802	870	850
Impairment and restructuring charges, and acquisition-related costs	209	541	202
Litigation and investigation costs	38	23	293
Net gains on sales, consolidation and deconsolidation of facilities	(127)	(144)	(151)
Operating income	1,647	1,113	1,247
Interest expense	(1,004)	(1,028)	(979)
Other non-operating expense, net	(5)	(22)	(20)
Gain (loss) from early extinguishment of debt	1	(164)	0
Income (loss) from continuing operations, before income taxes	639	(101)	248
Income tax expense	(176)	(219)	(67)
Income (loss) from continuing operations, before discontinued operations	463	(320)	181
Discontinued operations:
Income (loss) from operations	4	0	(6)
Income tax benefit (expense)	(1)	0	1
Income (loss) from discontinued operations	3	0	(5)
Net income (loss)	466	(320)	176
Less: Net income available to noncontrolling interests	355	384	368
Net income available (loss attributable) to Tenet Healthcare Corporation common shareholders	111	(704)	(192)
Amounts available (attributable) to Tenet Healthcare Corporation common shareholders
Income (loss) from continuing operations, net of tax	108	(704)	(187)
Income (loss) from discontinued operations, net of tax	3	0	(5)
Net income available (loss attributable) to Tenet Healthcare Corporation common shareholders	$ 111	$ (704)	$ (192)
Basic
Continuing operations (in usd per share)	$ 1.06	$ (7)	$ (1.88)
Discontinued operations (in usd per share)	0.03	0	(0.05)
Total loss per share, Basic (in usd per share)	1.09	(7)	(1.93)
Diluted
Continuing operations (in usd per share)	1.04	(7)	(1.88)
Discontinued operations (in usd per share)	0.03	0	(0.05)
Total loss per share, Diluted (in usd per share)	$ 1.07	$ (7)	$ (1.93)
Weighted average shares and dilutive securities outstanding (in thousands):
Basic (in shares)	102,110	100,592	99,321
Diluted (in shares)	103,881	100,592	99,321

CONSOLIDATED STATEMENTS OF OTHE

CONSOLIDATED STATEMENTS OF OTHER COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 466	$ (320)	$ 176
Other comprehensive income (loss):
Adjustments for defined benefit plans	(29)	42	(73)
Amortization of net actuarial loss included in other non-operating expense, net	14	14	12
Unrealized gains (losses) on debt securities held as available-for-sale	0	6	2
Sale of foreign subsidiary	37	0	0
Foreign currency translation adjustments	(4)	15	(53)
Other comprehensive income (loss) before income taxes	18	77	(112)
Income tax benefit (expense) related to items of other comprehensive income (loss)	6	(23)	18
Total other comprehensive income (loss), net of tax	24	54	(94)
Comprehensive net income (loss)	490	(266)	82
Less: Comprehensive income attributable to noncontrolling interests	355	384	368
Comprehensive income available (loss attributable) to Tenet Healthcare Corporation common shareholders	$ 135	$ (650)	$ (286)

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) shares in Thousands, $ in Millions	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit	Treasury Stock	Noncontrolling Interests
Beginning balance (in shares) at Dec. 31, 2015		98,495
Beginning balance at Dec. 31, 2015	$ 958	$ 7	$ 4,815	$ (164)	$ (1,550)	$ (2,417)	$ 267
Changes in Shareholders' Equity
Net income (loss)	(54)				(192)		138
Distributions paid to noncontrolling interests	(111)						(111)
Other comprehensive income (loss)	(94)			(94)
Purchases (sales) of businesses and noncontrolling interests	106		(40)				146
Purchase accounting adjustments	225						225
Stock-based compensation expense, tax benefit and issuance of common stock (in shares)		1,191
Stock-based compensation expense, tax benefit and issuance of common stock	52		52
Ending balance (in shares) at Dec. 31, 2016		99,686
Ending balance at Dec. 31, 2016	1,082	$ 7	4,827	(258)	(1,742)	(2,417)	665
Changes in Shareholders' Equity
Net income (loss)	(559)				(704)		145
Distributions paid to noncontrolling interests	(123)						(123)
Other comprehensive income (loss)	54			54
Accretion of redeemable noncontrolling interests	(33)		(33)
Purchases (sales) of businesses and noncontrolling interests	3		4				(1)
Stock-based compensation expense, tax benefit and issuance of common stock (in shares)		1,286
Stock-based compensation expense, tax benefit and issuance of common stock	59		61			(2)
Ending balance (in shares) at Dec. 31, 2017		100,972
Ending balance at Dec. 31, 2017	539	$ 7	4,859	(204)	(2,390)	(2,419)	686
Changes in Shareholders' Equity
Net income (loss)	276				111		165
Distributions paid to noncontrolling interests	(148)						(148)
Other comprehensive income (loss)	24			24
Accretion of redeemable noncontrolling interests	(173)		(173)
Purchases (sales) of businesses and noncontrolling interests	106		3				103
Stock-based compensation expense, tax benefit and issuance of common stock (in shares)		1,565
Stock-based compensation expense, tax benefit and issuance of common stock	63		58			5
Ending balance (in shares) at Dec. 31, 2018		102,537
Ending balance at Dec. 31, 2018	$ 687	$ 7	$ 4,747	$ (223)	$ (2,236)	$ (2,414)	$ 806

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Cash Flows [Abstract]
Net income (loss)	$ 466	$ (320)	$ 176
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	802	870	850
Provision for doubtful accounts	0	1,434	1,449
Deferred income tax expense	150	200	41
Stock-based compensation expense	46	59	68
Impairment and restructuring charges, and acquisition-related costs	209	541	202
Litigation and investigation costs	38	23	293
Net gains on sales, consolidation and deconsolidation of facilities	(127)	(144)	(151)
Loss (gain) from early extinguishment of debt	(1)	164	0
Equity in earnings of unconsolidated affiliates, net of distributions received	(12)	(18)	(13)
Amortization of debt discount and debt issuance costs	45	44	41
Pre-tax loss (income) from discontinued operations	(4)	0	6
Other items, net	(21)	(18)	(1)
Changes in cash from operating assets and liabilities:
Accounts receivable	(134)	(1,448)	(1,604)
Inventories and other current assets	17	(35)	(83)
Income taxes	(3)	(38)	(8)
Accounts payable, accrued expenses and other current liabilities	(152)	(10)	(51)
Other long-term liabilities	(102)	26	40
Payments for restructuring charges, acquisition-related costs, and litigation costs and settlements	(163)	(125)	(691)
Net cash used in operating activities from discontinued operations, excluding income taxes	(5)	(5)	(6)
Net cash provided by operating activities	1,049	1,200	558
Cash flows from investing activities:
Purchases of property and equipment — continuing operations	(617)	(707)	(875)
Purchases of businesses or joint venture interests, net of cash acquired	(113)	(50)	(117)
Proceeds from sales of facilities and other assets	543	827	573
Proceeds from sales of marketable securities, long-term investments and other assets	199	36	62
Purchases of equity investments	(127)	(68)	(39)
Other long-term assets	15	(10)	(31)
Other items, net	(15)	(7)	(3)
Net cash provided by (used in) investing activities	(115)	21	(430)
Cash flows from financing activities:
Repayments of borrowings under credit facility	(950)	(970)	(1,895)
Proceeds from borrowings under credit facility	950	970	1,895
Repayments of other borrowings	(312)	(4,139)	(154)
Proceeds from other borrowings	23	3,795	760
Debt issuance costs	0	(62)	(12)
Distributions paid to noncontrolling interests	(288)	(258)	(218)
Proceeds from sale of noncontrolling interests	20	31	22
Purchases of noncontrolling interests	(647)	(729)	(186)
Proceeds from exercise of stock options and employee stock purchase plan	16	7	4
Other items, net	54	29	16
Net cash provided by (used in) financing activities	(1,134)	(1,326)	232
Net increase (decrease) in cash and cash equivalents	(200)	(105)	360
Cash and cash equivalents at beginning of period	611	716	356
Cash and cash equivalents at end of period	411	611	716
Supplemental disclosures:
Interest paid, net of capitalized interest	(976)	(939)	(932)
Income tax payments, net	$ (25)	$ (56)	$ (33)

SIGNIFICANT ACCOUNTING POLICIES

SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
SIGNIFICANT ACCOUNTING POLICIES	SIGNIFICANT ACCOUNTING POLICIES Description of Business Tenet Healthcare Corporation (together with our subsidiaries, referred to herein as “Tenet,” “we” or “us”) is a diversified healthcare services company. At December 31, 2018 , we operated 68 hospitals ( three of which we have since divested), 23 surgical hospitals and approximately 475 outpatient centers through our subsidiaries, partnerships and joint ventures, including USPI Holding Company, Inc. (“USPI”). We hold noncontrolling interests in 111 of these facilities, which are recorded using the equity method of accounting. Our Conifer Holdings, Inc. (“Conifer”) subsidiary provides healthcare business process services in the areas of hospital and physician revenue cycle management and value-based care solutions to healthcare systems, as well as individual hospitals, physician practices, self-insured organizations, health plans and other entities . Effective June 16, 2015, we completed a transaction that combined our freestanding ambulatory surgery and imaging center assets with the surgical facility assets of United Surgical Partners International, Inc. into our joint venture, USPI. In April 2016, we paid $127 million to purchase additional shares, which increased our ownership interest in USPI from 50.1% to approximately 56.3% . In July 2017, we paid $716 million for the purchase of additional shares and the final adjustment to the 2016 purchase price, which increased our ownership interest in USPI to 80.0% . In April 2018, we paid approximately $630 million for the purchase of an additional 15% ownership interest in USPI and the final adjustment to the 2017 purchase price, which increased our ownership interest in USPI to 95% . Basis of Presentation Our Consolidated Financial Statements include the accounts of Tenet and its wholly owned and majority-owned subsidiaries. We eliminate intercompany accounts and transactions in consolidation, and we include the results of operations of businesses that are newly acquired in purchase transactions from their dates of acquisition. We account for significant investments in other affiliated companies using the equity method. Unless otherwise indicated, all financial and statistical data included in these notes to our Consolidated Financial Statements relate to our continuing operations, with dollar amounts expressed in millions (except per-share amounts). Effective January 1, 2018, we adopted the Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2014-09, “Revenue from Contracts with Customers (Topic 606)” (“ASU 2014-09”) using a modified retrospective method of application to all contracts existing on January 1, 2018. The core principle of the guidance in ASU 2014-09 is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. For our Hospital Operations and other and Ambulatory Care segments, the adoption of ASU 2014-09 resulted in changes to our presentation and disclosure of revenue primarily related to uninsured or underinsured patients. Prior to the adoption of ASU 2014-09, a significant portion of our provision for doubtful accounts related to self-pay patients, as well as co-pays, co-insurance amounts and deductibles owed to us by patients with insurance. Under ASU 2014-09, the estimated uncollectable amounts due from these patients are generally considered implicit price concessions that are a direct reduction to net operating revenues, with a corresponding material reduction in the amounts presented separately as provision for doubtful accounts. For the year ended December 31, 2018 , we recorded approximately $1.422 billion of implicit price concessions as a direct reduction of net operating revenues that would have been recorded as provision for doubtful accounts prior to the adoption of ASU 2014-09. At January 1, 2018, we reclassified $171 million of revenues related to patients who were still receiving inpatient care in our facilities at that date from accounts receivable, less allowance for doubtful accounts, to contract assets, which are included in other current assets in the accompanying Consolidated Balance Sheet at December 31, 2018 . The adoption of ASU 2014-09 also resulted in changes to our presentation and disclosure of customer contract assets and liabilities and the assessment of variable consideration under customer contracts, which are further discussed in Note 4. Also effective January 1, 2018, we early adopted ASU 2018-02, “Income Statement – Reporting Comprehensive Income (Topic 220)” (“ASU 2018-02”), which allows a reclassification from accumulated other comprehensive income to retained earnings for stranded income tax effects resulting from the Tax Cuts and Jobs Act (the “Tax Act”) and requires certain disclosures about stranded income tax effects. We applied the amendments in ASU 2018-02 in the period of adoption, resulting in a reclassification that decreased accumulated deficit and increased accumulated other comprehensive loss by $36 million of stranded income tax effects in the year ended December 31, 2018. In addition, we adopted ASU 2016-01, “Financial Instruments – Overall (Subtopic 825-10) Recognition and Measurement of Financial Assets and Financial Liabilities” (“ASU 2016-01”) effective January 1, 2018, which supersedes the guidance to classify equity securities with readily determinable fair values into different categories (that is, trading or available-for-sale) and require equity securities (including other ownership interests, such as partnerships, unincorporated joint ventures and limited liability companies) to be measured at fair value with changes in the fair value recognized through net income. Upon adoption of ASU 2016-01 on January 1, 2018, we recorded a cumulative effect adjustment to decrease accumulated deficit by $7 million for unrealized gains on equity securities. Effective January 1, 2017, we adopted ASU 2016-09, “Compensation – Stock Compensation (Topic 718) Improvements to Employee Share-Based Payment Accounting” (“ASU 2016-09”), which affects all entities that issue share-based payment awards to their employees. The guidance in ASU 2016-09 simplifies several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. Upon adoption of ASU 2016-09, we recorded previously unrecognized excess tax benefits of $56 million as a deferred tax asset and a cumulative effect adjustment to accumulated deficit as of January 1, 2017. Prospectively, all excess tax benefits and deficiencies will be recognized as income tax benefit or expense in our consolidated statement of operations when awards vest. Also effective January 1, 2017, we early adopted ASU 2017-07, “Compensation – Retirement Benefits (Topic 715) Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost” (“ASU 2017-07”), which the FASB issued in March 2017. The amendments in ASU 2017-07 apply to all employers that offer to their employees defined benefit pension plans, other postretirement benefit plans, or other types of benefits accounted for under Topic 715 of the FASB Accounting Standards Codification (“ASC”). The guidance in ASU 2017-07 requires that an employer report the service cost component in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period. The other components of net periodic benefit cost are required to be presented in the statement of operations separately from the service cost component and outside a subtotal of income from operations. The line item or items used in the statement of operations to present the other components of net periodic benefit cost must be disclosed. The amendments in ASU 2017-07 must be applied retrospectively for the presentation of the service cost component and the other components of net periodic pension cost and net periodic postretirement benefit cost in the statement of operations. As a result of the adoption of ASU 2017-07, we reclassified $28 million of net periodic benefit cost from salaries, wages and benefits expense to other non-operating expense, net, in the accompanying Consolidated Statements of Operations for the year ended December 31, 2016, and $16 million and $31 million of other components of net periodic benefit cost are included in other non-operating expense, net, in the accompanying Consolidated Statement of Operations for the years ended December 31, 2018 and 2017 , respectively. Certain prior-year amounts have also been reclassified to conform to current year presentation, primarily related to the format of disclosures in Note 14 that have been revised due to the adoption of ASU 2014-09 and the reclassification of previously held equity method investment changes due to acquisitions presented in Note 21. Use of Estimates The preparation of financial statements, in conformity with accounting principles generally accepted in the United States of America (“GAAP”), requires us to make estimates and assumptions that affect the amounts reported in our Consolidated Financial Statements and these accompanying notes. We regularly evaluate the accounting policies and estimates we use. In general, we base the estimates on historical experience and on assumptions that we believe to be reasonable given the particular circumstances in which we operate. Although we believe all adjustments considered necessary for a fair presentation have been included, actual results may vary from those estimates. Financial and statistical information we report to other regulatory agencies may be prepared on a basis other than GAAP or using different assumptions or reporting periods and, therefore, may vary from amounts presented herein. Although we make every effort to ensure that the information we report to those agencies is accurate, complete and consistent with applicable reporting guidelines, we cannot be responsible for the accuracy of the information they make available to the public. Translation of Foreign Currencies We divested European Surgical Partners Limited (“Aspen”) in August 2018; prior to that time, Aspen’s accounts were measured in its local currency (the pound sterling) and then translated into U.S. dollars. All assets and liabilities were translated using the current rate of exchange at the balance sheet date. Results of operations were translated using the average rates prevailing throughout the period of operations. Translation gains or losses resulting from changes in exchange rates were accumulated in shareholders’ equity until we divested Aspen. Net Operating Revenues ASU 2014-09 was issued to clarify the principles for recognizing revenue, to remove inconsistencies and weaknesses in revenue recognition requirements, and to provide a more robust framework for addressing revenue issues. Our adoption of ASU 2014-09 was accomplished using a modified retrospective method of application, and our accounting policies related to revenues were revised accordingly effective January 1, 2018, as discussed below. We recognize net operating revenues in the period in which we satisfy our performance obligations under contracts by transferring our services to our customers. Net operating revenues are recognized in the amounts to which we expect to be entitled, which are the transaction prices allocated to the distinct services. Net operating revenues for our Hospital Operations and other and Ambulatory Care segments primarily consist of net patient service revenues, principally for patients covered by Medicare, Medicaid, managed care and other health plans, as well as certain uninsured patients under our Compact with Uninsured Patients (“ Compact ”) and other uninsured discount and charity programs. Net operating revenues for our Conifer segment primarily consist of revenues from providing revenue cycle management services to healthcare systems, as well as individual hospitals, physician practices, self-insured organizations, health plans and other entities. Net Patient Service Revenues— We report net patient service revenues at the amounts that reflect the consideration to which we expect to be entitled in exchange for providing patient care. These amounts are due from patients, third-party payers (including managed care payers and government programs) and others, and they include variable consideration for retroactive revenue adjustments due to settlement of audits, reviews and investigations. Generally, we bill our patients and third-party payers several days after the services are performed or shortly after discharge. Revenues are recognized as performance obligations are satisfied. We determine performance obligations based on the nature of the services we provide. We recognize revenues for performance obligations satisfied over time based on actual charges incurred in relation to total expected charges. We believe that this method provides a faithful depiction of the transfer of services over the term of performance obligations based on the inputs needed to satisfy the obligations. Generally, performance obligations satisfied over time relate to patients in our hospitals receiving inpatient acute care services. We measure performance obligations from admission to the point when there are no further services required for the patient, which is generally the time of discharge. We recognize revenues for performance obligations satisfied at a point in time, which generally relate to patients receiving outpatient services, when: (1) services are provided; and (2) we do not believe the patient requires additional services. Because our patient service performance obligations relate to contracts with a duration of less than one year, we have elected to apply the optional exemption provided in ASC 606-10-50-14(a) and, therefore, we are not required to disclose the aggregate amount of the transaction price allocated to performance obligations that are unsatisfied or partially unsatisfied at the end of the reporting period. The unsatisfied or partially unsatisfied performance obligations referred to above are primarily related to inpatient acute care services at the end of the reporting period. The performance obligations for these contracts are generally completed when the patients are discharged, which generally occurs within days or weeks of the end of the reporting period. We determine the transaction price based on gross charges for services provided, reduced by contractual adjustments provided to third-party payers, discounts provided to uninsured patients in accordance with our Compact , and implicit price concessions provided primarily to uninsured patients. We determine our estimates of contractual adjustments and discounts based on contractual agreements, our discount policies and historical experience. We determine our estimate of implicit price concessions based on our historical collection experience with these classes of patients using a portfolio approach as a practical expedient to account for patient contracts as collective groups rather than individually. The financial statement effects of using this practical expedient are not materially different from an individual contract approach. Gross charges are retail charges. They are not the same as actual pricing, and they generally do not reflect what a hospital is ultimately paid and, therefore, are not displayed in our consolidated statements of operations. Hospitals are typically paid amounts that are negotiated with insurance companies or are set by the government. Gross charges are used to calculate Medicare outlier payments and to determine certain elements of payment under managed care contracts (such as stop-loss payments). Because Medicare requires that a hospital’s gross charges be the same for all patients (regardless of payer category), gross charges are what hospitals charge all patients prior to the application of discounts and allowances. Revenues under the traditional fee-for-service Medicare and Medicaid programs are based primarily on prospective payment systems. Retrospectively determined cost-based revenues under these programs, which were more prevalent in earlier periods, and certain other payments, such as Indirect Medical Education, Direct Graduate Medical Education, disproportionate share hospital and bad debt expense reimbursement, which are based on our hospitals’ cost reports, are estimated using historical trends and current factors. Cost report settlements under these programs are subject to audit by Medicare and Medicaid auditors and administrative and judicial review, and it can take several years until final settlement of such matters is determined and completely resolved. Because the laws, regulations, instructions and rule interpretations governing Medicare and Medicaid reimbursement are complex and change frequently, the estimates we record could change by material amounts. We have a system and estimation process for recording Medicare net patient service revenue and estimated cost report settlements. As a result, we record accruals to reflect the expected final settlements on our cost reports. For filed cost reports, we record the accrual based on those cost reports and subsequent activity, and record a valuation allowance against those cost reports based on historical settlement trends. The accrual for periods for which a cost report is yet to be filed is recorded based on estimates of what we expect to report on the filed cost reports, and a corresponding valuation allowance is recorded as previously described. Cost reports generally must be filed within five months after the end of the annual cost reporting period. After the cost report is filed, the accrual and corresponding valuation allowance may need to be adjusted. Settlements with third-party payers for retroactive revenue adjustments due to audits, reviews or investigations are considered variable consideration and are included in the determination of the estimated transaction price for providing patient care using the most likely outcome method. These settlements are estimated based on the terms of the payment agreement with the payer, correspondence from the payer and our historical settlement activity, including an assessment to ensure that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the retroactive adjustment is subsequently resolved. Estimated settlements are adjusted in future periods as adjustments become known (that is, new information becomes available), or as years are settled or are no longer subject to such audits, reviews and investigations. Revenues under managed care plans are based primarily on payment terms involving predetermined rates per diagnosis, per-diem rates, discounted fee-for-service rates and/or other similar contractual arrangements. These revenues are also subject to review and possible audit by the payers, which can take several years before they are completely resolved. The payers are billed for patient services on an individual patient basis. An individual patient’s bill is subject to adjustment on a patient-by-patient basis in the ordinary course of business by the payers following their review and adjudication of each particular bill. We estimate the discounts for contractual allowances at the individual hospital level utilizing billing data on an individual patient basis. At the end of each month, on an individual hospital basis, we estimate our expected reimbursement for patients of managed care plans based on the applicable contract terms. Contractual allowance estimates are periodically reviewed for accuracy by taking into consideration known contract terms, as well as payment history. We believe our estimation and review process enables us to identify instances on a timely basis where such estimates need to be revised. We do not believe there were any adjustments to estimates of patient bills that were material to our revenues. In addition, on a corporate-wide basis, we do not record any general provision for adjustments to estimated contractual allowances for managed care plans. Managed care accounts, net of contractual allowances recorded, are further reduced to their net realizable value through implicit price concessions based on historical collection trends for these payers and other factors that affect the estimation process. We know of no claims, disputes or unsettled matters with any payer that would materially affect our revenues for which we have not adequately provided in the accompanying Consolidated Financial Statements. Generally, patients who are covered by third-party payers are responsible for related co-pays, co-insurance and deductibles, which vary in amount. We also provide services to uninsured patients and offer uninsured patients a discount from standard charges. We estimate the transaction price for patients with co-pays, co-insurance and deductibles and for those who are uninsured based on historical collection experience and current market conditions. Under our Compact and other uninsured discount programs, the discount offered to certain uninsured patients is recognized as a contractual allowance, which reduces net operating revenues at the time the self-pay accounts are recorded. The uninsured patient accounts, net of contractual allowances recorded, are further reduced to their net realizable value at the time they are recorded through implicit price concessions based on historical collection trends for self-pay accounts and other factors that affect the estimation process. There are various factors that can impact collection trends, such as changes in the economy, which in turn have an impact on unemployment rates and the number of uninsured and underinsured patients, the volume of patients through our emergency departments, the increased burden of co-pays, co-insurance amounts and deductibles to be made by patients with insurance, and business practices related to collection efforts. These factors continuously change and can have an impact on collection trends and our estimation process. Subsequent changes to the estimate of the transaction price are generally recorded as adjustments to net patient service revenues in the period of the change. We have provided implicit price concessions, primarily to uninsured patients and patients with co-pays, co-insurance and deductibles. The implicit price concessions included in estimating the transaction price represent the difference between amounts billed to patients and the amounts we expect to collect based on our collection history with similar patients. Although outcomes vary, our policy is to attempt to collect amounts due from patients, including co-pays, co-insurance and deductibles due from patients with insurance, at the time of service while complying with all federal and state statutes and regulations, including, but not limited to, the Emergency Medical Treatment and Active Labor Act (“EMTALA”). Generally, as required by EMTALA, patients may not be denied emergency treatment due to inability to pay. Therefore, services, including the legally required medical screening examination and stabilization of the patient, are performed without delaying to obtain insurance information. In non-emergency circumstances or for elective procedures and services, it is our policy to verify insurance prior to a patient being treated; however, there are various exceptions that can occur. Such exceptions can include, for example, instances where (1) we are unable to obtain verification because the patient’s insurance company was unable to be reached or contacted, (2) a determination is made that a patient may be eligible for benefits under various government programs, such as Medicaid or Victims of Crime, and it takes several days or weeks before qualification for such benefits is confirmed or denied, and (3) under physician orders we provide services to patients that require immediate treatment. We also provide charity care to patients who are financially unable to pay for the healthcare services they receive. Most patients who qualify for charity care are charged a per-diem amount for services received, subject to a cap. Except for the per-diem amounts, our policy is not to pursue collection of amounts determined to qualify as charity care; therefore, we do not report these amounts in net operating revenues. Patient advocates from Conifer’s Medical Eligibility Program screen patients in the hospital to determine whether those patients meet eligibility requirements for financial assistance programs. They also expedite the process of applying for these government programs. Conifer Revenues— Our Conifer segment recognizes revenue from its contracts when Conifer’s performance obligations are satisfied, which is generally as services are rendered. Revenue is recognized in an amount that reflects the consideration to which Conifer expects to be entitled. At contract inception, Conifer assesses the services specified in its contracts with customers and identifies a performance obligation for each distinct contracted service. Conifer identifies the performance obligations and considers all the services provided under the contract. Conifer generally considers the following distinct services as separate performance obligations: • revenue cycle management services; • value-based care services; • patient communication and engagement services; • consulting services; and • other client-defined projects. Conifer’s contracts generally consist of fixed-price, volume-based or contingency-based fees. Conifer’s long-term contracts typically provide for Conifer to deliver recurring monthly services over a multi-year period. The contracts are typically priced such that Conifer’s monthly fee to its customer represents the value obtained by the customer in the month for those services. Such multi-year service contracts may have upfront fees related to transition or integration work performed by Conifer to set up the delivery for the ongoing services. Such transition or integration work typically does not result in a separately identifiable obligation; thus, the fees and expenses related to such work are deferred and recognized over the life of the related contractual service period. Revenue for fixed-priced contracts is typically recognized at the time of billing unless evidence suggests that the revenue is earned or Conifer’s obligations are fulfilled in a different pattern. Revenue for volume-based contracts is typically recognized as the services are being performed at the contractually billable rate, which is generally a percentage of collections or a percentage of client net patient revenue. Electronic Health Record Incentives Under certain provisions of the American Recovery and Reinvestment Act of 2009 (“ARRA”), federal incentive payments are available to hospitals, physicians and certain other professionals when they adopt, implement or upgrade (“AIU”) certified electronic health record (“EHR”) technology or become “meaningful users,” as defined under ARRA, of EHR technology in ways that demonstrate improved quality, safety and effectiveness of care. We recognize Medicaid EHR incentive payments in our consolidated statements of operations for the first payment year when: (1) CMS approves a state’s EHR incentive plan; and (2) our hospital or employed physician acquires certified EHR technology (i.e., when AIU criteria are met). Medicaid EHR incentive payments for subsequent payment years are recognized in the period during which the specified meaningful use criteria are met. We recognize Medicare EHR incentive payments when: (1) the specified meaningful use criteria are met; and (2) contingencies in estimating the amount of the incentive payments to be received are resolved. During the years ended December 31, 2018 , 2017 and 2016 , certain of our hospitals and physicians satisfied the CMS AIU and/or meaningful use criteria. As a result, we recognized $3 million , $9 million and $32 million of Medicare and Medicaid EHR incentive payments as a reduction to expense in the accompanying Consolidated Statement of Operations for the years ended December 31, 2018 , 2017 and 2016 , respectively. Cash and Cash Equivalents We treat highly liquid investments with original maturities of three months or less as cash equivalents. Cash and cash equivalents were $411 million and $611 million at December 31, 2018 and 2017 , respectively. At December 31, 2018 and 2017 , our book overdrafts were $288 million and $311 million , respectively, which were classified as accounts payable. At December 31, 2018 and 2017 , $177 million and $179 million , respectively, of total cash and cash equivalents in the accompanying Consolidated Balance Sheets were intended for the operations of our captive insurance subsidiaries, and $8 million and $30 million , respectively, of total cash and cash equivalents in the accompanying Consolidated Balance Sheets were intended for the operations of our health plan-related businesses. Also at December 31, 2018 and 2017 , we had $135 million and $117 million , respectively, of property and equipment purchases accrued for items received but not yet paid. Of these amounts, $114 million and $79 million , respectively, were included in accounts payable. During the years ended December 31, 2018 and 2017 , we recorded non-cancellable capital leases of $149 million and $162 million , respectively, primarily for equipment. Investments in Debt and Equity Securities Prior to the adoption of ASU 2016-01 on January 1, 2018, we classified investments in debt and equity securities as either available-for-sale, held-to-maturity or as part of a trading portfolio. At December 31, 2017, we had no significant investments in securities classified as either held-to-maturity or trading. We carried securities classified as available-for-sale at fair value. We reported their unrealized gains and losses, net of taxes, as accumulated other comprehensive income (loss) unless we determined that a loss was other-than-temporary, at which point we would record a loss in our consolidated statements of operations. We included realized gains or losses in our consolidated statements of operations based on the specific identification method. Subsequent to the adoption of ASU 2016-01 on January 1, 2018, we classify investments in debt securities as either available-for-sale, held-to-maturity or as part of a trading portfolio, but these classifications are no longer applicable to equity securities. At December 31, 2018 , we had no significant investments in debt securities classified as either held-to-maturity or trading. We carry debt securities classified as available-for-sale at fair value. We report their unrealized gains and losses, net of taxes, as accumulated other comprehensive income (loss) unless we determine that a loss is other-than-temporary, at which point we would record a loss in our consolidated statements of operations. We carry equity securities at fair value, and we report their unrealized gains and losses in other non-operating expense, net, in our consolidated statements of operations. We include realized gains or losses in our consolidated statements of operations based on the specific identification method. Investments in Unconsolidated Affiliates We control 227 of the facilities within our Ambulatory Care segment and, therefore, consolidate their results. We account for many of the facilities our Ambulatory Care segment operates ( 110 of 337 at December 31, 2018 ), as well as additional companies in which our Hospital Operations and other segment holds ownership interests, under the equity method as investments in unconsolidated affiliates and report only our share of net income as equity in earnings of unconsolidated affiliates in the accompanying Consolidated Statements of Operations. Summarized financial information for these equity method investees is included in the following table; among the equity method investees are four North Texas hospitals in which we held minority interests and that were operated by our Hospital Operations and other segment through the divestiture of these investments effective March 1, 2018. We recorded a gain of $11 million in the year ended December 31, 2018 due to the sales of our minority interest in these hospitals. For investments acqui

EQUITY

EQUITY	12 Months Ended
	Dec. 31, 2018
Stockholders' Equity Note [Abstract]
EQUITY	EQUITY Noncontrolling Interests Our noncontrolling interests balances at December 31, 2018 and 2017 in the accompanying Consolidated Statements of Changes in Equity were comprised of $112 million and $64 million , respectively, from our Hospital Operations and other segment, and $694 million and $622 million , respectively, from our Ambulatory Care segment. Our net income attributable to noncontrolling interests for the years ended December 31, 2018 , 2017 and 2016 were comprised of $8 million , $11 million and $11 million , respectively, from our Hospital Operations and other segment, and $157 million , $134 million and $127 million

ACCOUNTS RECEIVABLE

ACCOUNTS RECEIVABLE	12 Months Ended
	Dec. 31, 2018
Accounts Receivable Additional Disclosures [Abstract]
ACCOUNTS RECEIVABLE	ACCOUNTS RECEIVABLE The principal components of accounts receivable are shown in the table below: December 31, 2018 December 31, 2017 Continuing operations: Patient accounts receivable $ 2,427 $ 3,376 Allowance for doubtful accounts — (898 ) Estimated future recoveries 148 132 Net cost reports and settlements payable and valuation allowances 18 4 2,593 2,614 Discontinued operations 2 2 Accounts receivable, net $ 2,595 $ 2,616 Accounts that are pursued for collection through Conifer’s business offices are maintained on our hospitals’ books and reflected in patient accounts receivable. For patient accounts receivable resulting from revenue recognized prior to January 1, 2018, an allowance for doubtful accounts was established to reduce the carrying value of such receivables to their estimated net realizable value. Generally, we estimated this allowance based on the aging of our accounts receivable by hospital, our historical collection experience by hospital and for each type of payer, and other relevant factors. At December 31, 2017 , our allowance for doubtful accounts was 26.6% of our patient accounts receivable. Under the provisions of ASC 2014-09, which we adopted effective January 1, 2018, when we have an unconditional right to payment, subject only to the passage of time, the right is treated as a receivable. Patient accounts receivable, including billed accounts and unbilled accounts for which we have the unconditional right to payment, and estimated amounts due from third-party payers for retroactive adjustments, are receivables if our right to consideration is unconditional and only the passage of time is required before payment of that consideration is due. For patient accounts receivable subsequent to our adoption of ASU 2014-09 on January 1, 2018, the estimated uncollectable amounts are generally considered implicit price concessions that are a direct reduction to patient accounts receivable rather than allowance for doubtful accounts. Accounts assigned to Conifer are written off and excluded from patient accounts receivable; however, an estimate of future recoveries from all accounts at Conifer is determined based on historical experience and recorded on our hospitals’ books as a component of accounts receivable in the accompanying Consolidated Balance Sheets. We also provide charity care to patients who are financially unable to pay for the healthcare services they receive. Most patients who qualify for charity care are charged a per-diem amount for services received, subject to a cap. Except for the per-diem amounts, our policy is not to pursue collection of amounts determined to qualify as charity care; therefore, we do not report these amounts in net operating revenues. Most states include an estimate of the cost of charity care in the determination of a hospital’s eligibility for Medicaid disproportionate share hospital (“DSH”) payments. These payments are intended to mitigate our cost of uncompensated care, as well as reduced Medicaid funding levels. Generally, our method of measuring the estimated costs uses adjusted self-pay/charity patient days multiplied by selected operating expenses (which include salaries, wages and benefits, supplies and other operating expenses and which exclude the costs of our health plan businesses) per adjusted patient day. The adjusted self-pay/charity patient days represents actual self-pay/charity patient days adjusted to include self-pay/charity outpatient services by multiplying actual self-pay/charity patient days by the sum of gross self-pay/charity inpatient revenues and gross self-pay/charity outpatient revenues and dividing the results by gross self-pay/charity inpatient revenues. The table below shows our estimated costs of caring for our self-pay patients and charity care patients, as well as revenues attributable to Medicaid DSH and other supplemental revenues we recognized in the years ended December 31, 2018 , 2017 and 2016 . Years Ended December 31, 2018 2017 2016 Estimated costs for: Self-pay patients $ 640 $ 648 $ 609 Charity care patients 124 121 138 Total $ 764 $ 769 $ 747 Medicaid DSH and other supplemental revenues $ 847 $ 864 $ 906 We had $278 million and $231 million of receivables recorded in other current assets and investments and other assets, respectively, and $100 million and $42 million of payables recorded in other current liabilities and other long-term liabilities, respectively, in the accompanying Consolidated Balance Sheet at December 31, 2018 related to California’s provider fee program. We had $312 million and $266 million of receivables recorded in other current assets and investments and other assets, respectively, and $159 million and $49 million of payables recorded in other current liabilities and other long-term liabilities, respectively, in the accompanying Consolidated Balance Sheet at December 31, 2017

CONTRACT BALANCES (Notes)

CONTRACT BALANCES (Notes)	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
CONTRACT BALANCES	CONTRACT BALANCES Hospital Operations and Other Segment Under the provisions of ASU 2014-09, which we adopted effective January 1, 2018, amounts related to services provided to patients for which we have not billed and that do not meet the conditions of unconditional right to payment at the end of the reporting period are contract assets. For our Hospital Operations and other segment, our contract assets consist primarily of services that we have provided to patients who are still receiving inpatient care in our facilities at the end of the reporting period. Our Hospital Operations and other segment’s contract assets are included in other current assets in the accompanying Consolidated Balance Sheet at December 31, 2018. The opening and closing balances of contract assets for our Hospital Operations and other segment are as follows: 2018 2017 January 1, $ 171 $ — December 31, 169 — Increase/(decrease) $ (2 ) $ — The increase in the contract asset balances from the year ended December 31, 2018 compared to the year ended December 31, 2017 is due to the implementation of ASU 2014-09 effective January 1, 2018 using a modified retrospective method of application. Prior to January 1, 2018, amounts related to services provided to patients for which we had not billed were included in accounts receivable, less allowance for doubtful accounts, in our consolidated balance sheets. Approximately 89% of our Hospital Operations and other segment’s contract assets meet the conditions for unconditional right to payment and are reclassified to patient receivables within 90 days. Conifer Segment Conifer enters into contracts with customers to sell revenue cycle management and other services, such as value-based care, consulting and project services. The payment terms and conditions in our customer contracts vary. In some cases, customers are invoiced in advance and (for other than fixed-price fee arrangements) a true-up to the actual fee is included on a subsequent invoice. In other cases, payment is due in arrears. In addition, some contracts contain performance incentives, penalties and other forms of variable consideration. When the timing of Conifer’s delivery of services is different from the timing of payments made by the customers, Conifer recognizes either unbilled revenue (performance precedes contractual right to invoice the customer) or deferred revenue (customer payment precedes Conifer service performance). In the following table, customers that prepay prior to obtaining control/benefit of the service are represented by deferred contract revenue until the performance obligations are satisfied. Unbilled revenue represents arrangements in which Conifer has provided services to and the customer has obtained control/benefit of services prior to the contractual invoice date. Contracts with payment in arrears are recognized as receivables in the month the service is performed. The opening and closing balances of Conifer’s receivables, contract asset, and current and long-term contract liabilities are as follows: Contract Liability- Contract Liability- Contract Asset- Current Long-Term Receivables Unbilled Revenue Deferred Revenue Deferred Revenue January 1, 2018 $ 89 $ 10 $ 80 $ 21 December 31, 2018 42 11 61 20 Increase/(decrease) $ (47 ) $ 1 $ (19 ) $ (1 ) January 1, 2017 $ 67 $ 8 $ 76 $ 26 December 31, 2017 89 10 80 21 Increase/(decrease) $ 22 $ 2 $ 4 $ (5 ) The difference between the opening and closing balances of Conifer’s contract assets and contract liabilities are primarily related to prepayments for those customers who are billed in advance, changes in estimates related to metric-based services, and up-front integration services that are typically not distinct and are, therefore, recognized over the performance obligation period to which they relate. Our Conifer segment’s receivables and contract assets are reported as part of other current assets in our accompanying Consolidated Balance Sheets, and our Conifer segment’s current and long-term contract liabilities are reported as part of other current liabilities and other long-term liabilities, respectively, in our accompanying Consolidated Balance Sheets. The amount of revenue Conifer recognized in the years ended December 31, 2018 and 2017 that was included in the opening current deferred revenue liability was $72 million and $73 million , respectively. This revenue consists primarily of prepayments for those customers who are billed in advance, changes in estimates related to metric-based services, and up-front integration services that are recognized over the services period. Contract Costs We have elected to apply the practical expedient provided by ASC 340-40-25-4 and expense as incurred the incremental customer contract acquisition costs for contracts in which the amortization period of the asset that we otherwise would have recognized is one year or less. However, incremental costs incurred to obtain and fulfill customer contracts for which the amortization period of the asset that we otherwise would have recognized is longer than one year, which consist primarily of Conifer deferred contract setup costs, are capitalized and amortized on a straight-line basis over the lesser of their estimated useful lives or the term of the related contract. During the years ended December 31, 2018 , 2017 and 2016 , we recognized amortization expense of $11 million , $10 million and 7 million , respectively. At December 31, 2018 and 2017 , the unamortized customer contract costs were $28 million and $35 million Net operating revenues for our Hospital Operations and other and Ambulatory Care segments primarily consist of net patient service revenues, principally for patients covered by Medicare, Medicaid, managed care and other health plans, as well as certain uninsured patients under our Compact and other uninsured discount and charity programs. Net operating revenues for our Conifer segment primarily consist of revenues from providing revenue cycle management services to healthcare systems, as well as individual hospitals, physician practices, self-insured organizations, health plans and other entities. The table below shows our sources of net operating revenues less provision for doubtful accounts and implicit price concessions from continuing operations: Years Ended December 31, 2018 2017 2016 Hospital Operations and other: Net patient service revenues from hospitals and related Medicare $ 2,882 $ 3,243 $ 3,386 Medicaid 1,294 1,304 1,346 Managed care 9,213 9,583 9,728 Self-pay 96 91 63 Indemnity and other 596 608 604 Total 14,081 14,829 15,127 Physician practices revenues 1,097 1,209 1,201 Health plans 14 110 482 Revenue from other sources 93 112 94 Hospital Operations and other total prior to 15,285 16,260 16,904 Ambulatory Care 2,085 1,940 1,797 Conifer 1,533 1,597 1,571 Inter-segment eliminations (590 ) (618 ) (651 ) Net operating revenues $ 18,313 $ 19,179 $ 19,621 Adjustments for prior-year cost reports and related valuation allowances, principally related to Medicare and Medicaid, increased revenues in the years ended December 31, 2018 , 2017 and 2016 by $24 million , $35 million and $54 million , respectively. Estimated cost report settlements and valuation allowances are included in accounts receivable in the accompanying Consolidated Balance Sheets (see Note 3). We believe that we have made adequate provision for any adjustments that may result from final determination of amounts earned under all the above arrangements with Medicare and Medicaid. The table below shows the composition of net operating revenues less provision for doubtful accounts and implicit price concessions for our Ambulatory Care segment: Years Ended December 31, 2018 2017 2016 Net patient service revenues $ 1,965 $ 1,816 $ 1,684 Management fees 92 93 89 Revenue from other sources 28 31 24 Net operating revenues $ 2,085 $ 1,940 $ 1,797 The table below shows the composition of net operating revenues for our Conifer segment: Years Ended December 31, 2018 2017 2016 Revenue cycle services – Tenet $ 568 $ 583 $ 596 Revenue cycle services – other customers 855 891 839 Other services – Tenet 22 35 55 Other services – other customers 88 88 81 Total revenues from client contracts $ 1,533 $ 1,597 $ 1,571 Other services represent 7% of Conifer’s revenue and include value-based care, consulting and project services. Performance Obligations The following table includes Conifer’s revenue that is expected to be recognized in the future related to performance obligations that are unsatisfied, or partially unsatisfied, at the end of the reporting period. The amounts in the table primarily consist of revenue cycle management fixed fees, which are typically recognized ratably as the performance obligation is satisfied. The estimated revenue does not include volume or contingency based contracts, performance incentives, penalties or other variable consideration that is considered constrained. Conifer’s contract with Catholic Health Initiatives (“CHI”), a minority interest owner of Conifer Health Solutions, LLC, represents the majority of the fixed-fee revenue related to remaining performance obligations. Conifer’s contract term with CHI ends in 2032. Years Ending December 31, Later Years Total 2019 2020 2021 2022 2023 Performance obligations $ 7,736 $ 585 $ 584 $ 581 $ 581 $ 581 $ 4,824

ASSETS AND LIABILITIES HELD FOR

ASSETS AND LIABILITIES HELD FOR SALE	12 Months Ended
	Dec. 31, 2018
Discontinued Operation, Additional Disclosures [Abstract]
ASSETS AND LIABILITIES HELD FOR SALE	ASSETS AND LIABILITIES HELD FOR SALE In the three months ended December 31, 2017, three of our hospitals in the Chicago area, as well as other operations affiliated with the hospitals, met the criteria to be classified as held for sale. As a result, we have classified these assets totaling $107 million as “assets held for sale” in current assets and the related liabilities of $43 million as “liabilities held for sale” in current liabilities in the accompanying Consolidated Balance Sheet at December 31, 2018 . These assets and liabilities, which were in our Hospital Operations and other segment until their divestiture on January 28, 2019, were recorded at the lower of their carrying amount or their fair value less estimated costs to sell. We recorded impairment charges of $24 million and $73 million in the years ended December 31, 2018 and December 31, 2017 , respectively, for the write-down of the assets held for sale to their estimated fair value, less estimated costs to sell, as a result of the planned divestiture of these assets. Assets and liabilities classified as held for sale at December 31, 2018 were comprised of the following: Accounts receivable $ 54 Other current assets 13 Investments and other long-term assets 1 Property and equipment 39 Current liabilities (36 ) Long-term liabilities (7 ) Net assets held for sale $ 64 In the three months ended December 31, 2018, we completed the sale of certain assets and the related liabilities of our health plan in California; these assets and the related liabilities were classified as held for sale in the three months ended December 31, 2017. As a result of this transaction, we recorded a gain on sale of $36 million and received net pre-tax cash proceeds of $53 million in the year ended December 31, 2018 . In the three months ended September 30, 2018, we completed the sale of our nine Aspen facilities in the United Kingdom for net pre-tax cash proceeds of approximately $15 million ; these assets met the criteria to be classified as held for sale in the three months ended September 30, 2017. We recorded impairment charges related to this transaction of $9 million and $59 million in the years ended December 31, 2018 and 2017, respectively, for the write-down of assets held for sale to their estimated fair value, less estimated costs to sell. In the three months ended June 30, 2018, we completed the sale of our hospital, physician practices and other hospital-affiliated operations in St. Louis, Missouri; these assets met the criteria to be classified as held for sale in the three months ended December 31, 2017. As a result of this transaction, we recorded a gain on sale of $12 million and received net pre-tax cash proceeds of $54 million in the three months ended June 30, 2018. In the three months ended March 31, 2018, we completed the sale of MacNeal Hospital, which is located in a suburb of Chicago, and other operations affiliated with the hospital; these assets met the criteria to be classified as held for sale in the three months ended September 30, 2017. As a result of this transaction, we recorded a gain on sale of $90 million and received net pre-tax cash proceeds of $241 million after post-closing adjustments in the year ended December 31, 2018 . Also in the three months ended March 31, 2018, we completed the sale of our hospitals, physician practices and related assets in Philadelphia, Pennsylvania and the surrounding area; these assets met the criteria to be classified as held for sale in the three months ended September 30, 2017. As a result of the transaction, we recorded a loss on sale of $21 million and received net pre-tax proceeds of $132 million in cash after post-closing adjustments and a secured promissory note for $17.5 million in the year ended December 31, 2018. We recorded impairment charges related to this transaction of $232 million in the year ended December 31, 2017 for the write-down of assets held for sale to their estimated fair value, less estimated costs to sell. The real estate related to Abrazo Maryvale Hospital in Arizona, which we closed in December 2017, was divested in the three months ended March 31, 2018, resulting in net pre-tax proceeds of $7 million . The real estate was classified as held for sale in the three months ended December 31, 2017. In the three months ended September 30, 2017, we completed the sale of our hospitals, physician practices and related assets in Houston, Texas and the surrounding area for net proceeds of approximately $750 million ; these assets met the criteria to be classified as held for sale in the three months ended June 30, 2017. We recognized a gain on sale related to this transaction of $111 million in the year ended December 31, 2017. We recorded a loss on sale of $10 million for post-closing adjustments related to this transaction in the year ended December 31, 2018. The following table provides information on significant components of our business that have been recently disposed of or are classified as held for sale at December 31, 2018: Years Ended December 31, 2018 2017 2016 Significant disposals: Income (loss) from continuing operations, before income taxes Houston (includes a $111 million gain on sale in the 2017 period) $ (10 ) $ 133 $ 67 Philadelphia (includes $232 million of impairment charges in the 2017 period) $ (29 ) $ (255 ) $ (75 ) MacNeal (includes a $90 million gain on sale in the 2018 period) 93 27 29 Aspen (includes $59 million of impairment charges in the 2017 period) $ (6 ) $ (68 ) $ (16 ) Total 48 (163 ) 5 Significant planned divestitures classified as held for sale: Loss from continuing operations, before income taxes Chicago area (includes $24 million of impairment charges in the 2018 period and $73 million in the 2017 period) (41 ) (82 ) (1 ) Total $ (41 ) $ (82 ) $ (1 ) During the year ended December 31, 2017, we completed the sales of certain of our health plan businesses (or the membership thereof) in Michigan, Arizona and Texas at transaction prices of $20 million , $13 million and $12 million , respectively, and recognized gains on the sales of $3 million , $13 million and $10 million , respectively. These assets met the criteria to be classified as held for sale in the three months ended September 30, 2016. During the year ended December 31, 2016, we completed the sale of our hospitals, physician practices and related assets in Georgia at a transaction price of approximately $575 million and recognized a gain on sale of $113 million

IMPAIRMENT AND RESTRUCTURING CH

IMPAIRMENT AND RESTRUCTURING CHARGES, AND ACQUISITION-RELATED COSTS	12 Months Ended
	Dec. 31, 2018
Restructuring Costs and Asset Impairment Charges [Abstract]
IMPAIRMENT AND RESTRUCTURING CHARGES, AND ACQUISITION-RELATED COSTS	IMPAIRMENT AND RESTRUCTURING CHARGES, AND ACQUISITION-RELATED COSTS We recognized impairment charges on long-lived assets in 2018 , 2017 and 2016 because the fair values of those assets or groups of assets indicated that the carrying amount was not recoverable. The fair value estimates were derived from appraisals, established market values of comparable assets, or internal estimates of future net cash flows. These fair value estimates can change by material amounts in subsequent periods. Many factors and assumptions can impact the estimates, including the future financial results of the hospitals, how the hospitals are operated in the future, changes in healthcare industry trends and regulations, and the nature of the ultimate disposition of the assets. In certain cases, these fair value estimates assume the highest and best use of hospital assets in the future to a market place participant is other than as a hospital. In these cases, the estimates are based on the fair value of the real property and equipment if utilized other than as a hospital. The impairment recognized does not include the costs of closing the hospitals or other future operating costs, which could be substantial. Accordingly, the ultimate net cash realized from the hospitals, should we choose to sell them, could be significantly less than their impaired value. Our impairment tests presume stable, improving or, in some cases, declining operating results in our facilities, which are based on programs and initiatives being implemented that are designed to achieve the facility’s most recent projections. If these projections are not met, or if in the future negative trends occur that impact our future outlook, impairments of long-lived assets and goodwill may occur, and we may incur additional restructuring charges, which could be material. At December 31, 2018 , our continuing operations consisted of three reportable segments, Hospital Operations and other, Ambulatory Care and Conifer. Our segments are reporting units used to perform our goodwill impairment analysis. We completed our annual impairment tests for goodwill as of October 1, 2018. During the year ended December 31, 2017, we changed our annual quantitative goodwill impairment testing date from December 31 to October 1 of each year. The change in the goodwill impairment test date better aligns the impairment testing procedures with the timing of our long-term planning process, which is a significant input to the testing. Also, during January 2017, our Florida, Northeast and Southern regions and our Detroit market were combined to form our then Eastern region. Subsequent to this change, our Hospital Operations and other segment was comprised of our then Eastern, Texas and Western regions, which were our reporting units used to perform our goodwill impairment analysis. During October 2017, we further reorganized our business such that our regional management layer was eliminated. Due to this reorganization, our previous region reporting units for our Hospital Operations and other segment were combined into one reporting unit. The change in testing date and the change in reporting units did not delay, accelerate or avoid a goodwill impairment charge. We periodically incur costs to implement restructuring efforts for specific operations, which are recorded in our statement of operations as they are incurred. Our restructuring plans focus on various aspects of operations, including aligning our operations in the most strategic and cost-effective structure. Certain restructuring and acquisition-related costs are based on estimates. Changes in estimates are recognized as they occur. Year Ended December 31, 2018 During the year ended December 31, 2018 , we recorded impairment and restructuring charges and acquisition-related costs of $209 million , consisting of $77 million of impairment charges , $115 million of restructuring charges and $17 million of acquisition-related costs. Impairment charges included $40 million for the write-down of buildings and other long-lived assets to their estimated fair values at two hospitals. Material adverse trends in our most recent estimates of future undiscounted cash flows of the hospitals indicated the carrying value of the hospitals’ long-lived assets was not recoverable from the estimated future cash flows. We believe the most significant factors contributing to the adverse financial trends included reductions in volumes of insured patients, shifts in payer mix from commercial to governmental payers combined with reductions in reimbursement rates from governmental payers, and high levels of uninsured patients. As a result, we updated the estimate of the fair value of the hospitals’ long-lived assets and compared the fair value estimate to the carrying value of the hospitals’ long-lived assets. Because the fair value estimates were lower than the carrying value of the long-lived assets, an impairment charge was recorded for the difference in the amounts. The aggregate carrying value of assets held and used of the hospitals for which impairment charges were recorded was $130 million at December 31, 2018 after recording the impairment charges. We also recorded $24 million of charges to write-down assets held for sale to their estimated fair value, less estimated costs to sell, for certain of our Chicago-area facilities , $9 million of charges to write-down assets held for sale to their estimated fair value, less estimated costs to sell, for Aspen and $4 million of other impairment charges. Of the total impairment charges recognized for the year ended December 31, 2018 , $67 million related to our Hospital Operations and other segment, $9 million related to our Ambulatory Care segment, and $1 million related to our Conifer segment. Restructuring charges consisted of $68 million of employee severance costs , $17 million of contract and lease termination fees , and $30 million of other restructuring costs . Acquisition-related costs consisted of $10 million of transaction costs and $7 million of acquisition integration charges . Year Ended December 31, 2017 During the year ended December 31, 2017 , we recorded impairment and restructuring charges and acquisition-related costs of $541 million , consisting of $402 million of impairment charges, $117 million of restructuring charges and $22 million of acquisition-related costs. Impairment charges consisted of $364 million of charges to write-down assets held for sale to their estimated fair value, less estimated costs to sell, for Aspen, our Philadelphia-area facilities and certain of our Chicago-area facilities, $31 million for the impairment of two equity method investments and $7 million to write-down intangible assets. Of the total impairment charges recognized for the year ended December 31, 2017 , $337 million related to our Hospital Operations and other segment, $63 million related to our Ambulatory Care segment, and $2 million related to our Conifer segment. Restructuring charges consisted of $82 million of employee severance costs, $15 million of contract and lease termination fees, and $20 million of other restructuring costs. Acquisition-related costs consisted of $6 million of transaction costs and $16 million of acquisition integration charges. Year Ended December 31, 2016 During the year ended December 31, 2016 , we recorded impairment and restructuring charges and acquisition-related costs of $202 million . This amount included impairment charges of $54 million for the write-down of buildings, equipment and other long-lived assets, primarily capitalized software costs classified as other intangible assets, to their estimated fair values at four hospitals. Material adverse trends in our estimates of future undiscounted cash flows of the hospitals at that time indicated the carrying value of the hospitals’ long-lived assets was not recoverable from the estimated future cash flows. We believe the most significant factors contributing to the adverse financial trends included reductions in volumes of insured patients, shifts in payer mix from commercial to governmental payers combined with reductions in reimbursement rates from governmental payers, and high levels of uninsured patients. As a result, we updated the estimate of the fair value of the hospitals’ long-lived assets and compared the fair value estimate to the carrying value of the hospitals’ long-lived assets. Because the fair value estimates were lower than the carrying value of the long-lived assets, an impairment charge was recorded for the difference in the amounts. The aggregate carrying value of assets held and used of the hospitals for which impairment charges were recorded was $163 million at December 31, 2016 after recording the impairment charges. We also recorded $19 million of impairment charges related to investments and $14 million related to other intangible assets, primarily contract-related intangibles and capitalized software costs not associated with the hospitals described above. Of the total impairment charges recognized for the year ended December 31, 2016 , $76 million related to our Hospital Operations and other segment, $8 million related to our Ambulatory Care segment, and $3 million related to our Conifer segment. We also recorded $35 million of employee severance costs, $14 million of restructuring costs, $14 million of contract and lease termination fees, and $52 million in acquisition-related costs, which include $20 million of transaction costs and $32 million of acquisition integration costs.

LONG-TERM DEBT AND LEASE OBLIGA

LONG-TERM DEBT AND LEASE OBLIGATIONS	12 Months Ended
	Dec. 31, 2018
Long-term Debt and Capital Lease Obligations [Abstract]
LONG-TERM DEBT AND LEASE OBLIGATIONS	LONG-TERM DEBT AND LEASE OBLIGATIONS The table below shows our long-term debt as of December 31, 2018 and 2017 : December 31, 2018 December 31, 2017 Senior unsecured notes: 5.500% due 2019 $ 468 $ 500 6.750% due 2020 300 300 8.125% due 2022 2,800 2,800 6.750% due 2023 1,872 1,900 7.000% due 2025 478 500 6.875% due 2031 362 430 Senior secured first lien notes: 4.750% due 2020 500 500 6.000% due 2020 1,800 1,800 4.500% due 2021 850 850 4.375% due 2021 1,050 1,050 4.625% due 2024 1,870 1,870 Senior secured second lien notes: 7.500% due 2022 750 750 5.125% due 2025 1,410 1,410 Capital leases 425 431 Mortgage notes 75 77 Unamortized issue costs, note discounts and premiums (184 ) (231 ) Total long-term debt 14,826 14,937 Less current portion 182 146 Long-term debt, net of current portion $ 14,644 $ 14,791 Credit Agreement We have a senior secured revolving credit facility (as amended, the “Credit Agreement”) that provides, subject to borrowing availability, for revolving loans in an aggregate principal amount of up to $1 billion , with a $300 million subfacility for standby letters of credit. Obligations under the Credit Agreement, which has a scheduled maturity date of December 4, 2020, are guaranteed by substantially all of our domestic wholly owned hospital subsidiaries and are secured by a first-priority lien on the accounts receivable owned by us and the subsidiary guarantors. Outstanding revolving loans accrue interest at a base rate plus a margin ranging from 0.25% to 0.75% per annum or the London Interbank Offered Rate (“LIBOR”) plus a margin ranging from 1.25% to 1.75% per annum, in each case based on available credit. An unused commitment fee payable on the undrawn portion of the revolving loans ranges from 0.25% to 0.375% per annum based on available credit. Our borrowing availability is based on a specified percentage of eligible accounts receivable, including self-pay accounts . At December 31, 2018 , we were in compliance with all covenants and conditions in our Credit Agreement. At December 31, 2018 , we had no cash borrowings outstanding under the Credit Agreement and we had $2 million of standby letters of credit outstanding. Based on our eligible receivables, $998 million was available for borrowing under the Credit Agreement at December 31, 2018 . Our Credit Agreement contains provisions that limit the payment of cash dividends on our common stock if we do not meet certain financial ratios. Letter of Credit Facility We have a letter of credit facility (as amended, the “LC Facility”) that provides for the issuance of standby and documentary letters of credit, from time to time, in an aggregate principal amount of up to $180 million (subject to increase to up to $200 million ). The maturity date of the LC Facility is March 7, 2021. Obligations under the LC Facility are guaranteed and secured by a first-priority pledge of the capital stock and other ownership interests of certain of our wholly owned domestic hospital subsidiaries on an equal ranking basis with our senior secured first lien notes. Drawings under any letter of credit issued under the LC Facility that we have not reimbursed within three business days after notice thereof accrue interest at a base rate plus a margin equal to 0.50% per annum. An unused commitment fee is payable at an initial rate of 0.25% per annum with a step up to 0.375% per annum should our secured debt-to-EBITDA ratio equal or exceed 3.00 to 1.00 at the end of any fiscal quarter. A fee on the aggregate outstanding amount of issued but undrawn letters of credit accrues at a rate of 1.50% per annum. An issuance fee equal to 0.125% per annum of the aggregate face amount of each outstanding letter of credit is payable to the account of the issuer of the related letter of credit. At December 31, 2018 , we were in compliance with all covenants and conditions in our LC Facility. At December 31, 2018 , we had $93 million of standby letters of credit outstanding under the LC Facility. Senior Secured Notes and Senior Unsecured Notes In December 2018 and November 2018, we purchased $22 million and $10 million , respectively, of aggregate principal amount of our 5.500% senior unsecured notes due 2019 for $22 million and $10 million , respectively. In August 2018, we purchased $38 million aggregate principal amount of our 6.875% senior unsecured notes due 2031 for $36 million , including $1 million in accrued and unpaid interest through the dates of purchase. In May 2018, we purchased $30 million aggregate principal amount of our 6.875% senior unsecured notes due 2031 for $28 million . In connection with the purchase, we recorded a loss from early extinguishment of debt of $1 million in the three months ended June 30, 2018, primarily related to the write-off of associated unamortized note discount and issuance costs, partially offset by the difference between the purchase price and the par value of the notes. In March 2018, we purchased $28 million aggregate principal amount of our 6.750% senior unsecured notes due 2023 and $22 million aggregate principal amount of our 7.000% senior unsecured notes due 2025 for $51 million , including $1 million in accrued and unpaid interest through the dates of purchase. In connection with these purchases, we recorded a loss from early extinguishment of debt of $1 million in the three months ended March 31, 2018, primarily related to the write-off of associated unamortized issuance costs. On June 14, 2017, we sold $830 million aggregate principal amount of our 4.625% senior secured first lien notes, which will mature on July 15, 2024 (the “2024 Secured First Lien Notes”) . We will pay interest on the 2024 Secured First Lien Notes semi-annually in arrears on January 15 and July 15 of each year, which payments commenced on January 15, 2018. The proceeds from the sale of the 2024 Secured First Lien Notes were used, after payment of fees and expenses, together with cash on hand, to deposit with the trustee an amount sufficient to fund the redemption of all $900 million in aggregate principal amount of our outstanding floating rate senior secured notes due 2020 (the “2020 Floating Rate Notes”) on July 14, 2017, thereby fully discharging the 2020 Floating Rate Notes as of June 14, 2017. In connection with the redemption, we recorded a loss from early extinguishment of debt of $26 million in the three months ended June 30, 2017, primarily related to the difference between the redemption price and the par value of the notes, as well as the write-off of associated unamortized note discounts and issuance costs. Also on June 14, 2017, THC Escrow Corporation III (“ Escrow Corp. ”), a Delaware corporation established for the purpose of issuing the securities referred to in this paragraph, issued $1.040 billion in aggregate principal amount of 4.625% senior secured first lien notes due 2024 (the “Escrow Secured First Lien Notes”) , $1.410 billion in aggregate principal amount of 5.125% senior secured second lien notes due 2025 (the “Escrow Secured Second Lien Notes”) and $500 million in aggregate principal amount of 7.000% senior unsecured notes due 2025 (the “Escrow Unsecured Notes”) . On July 14, 2017, we (i) assumed Escrow Corp.’s obligations with respect to the Escrow Secured Second Lien Notes and (ii) effected a mandatory exchange of all outstanding Escrow Secured First Lien Notes for a like principal amount of our newly issued 2024 Secured First Lien Notes. The proceeds from the sale of the Escrow Secured Second Lien Notes and Escrow Secured First Lien Notes were released from escrow on July 14, 2017 and were used, after payment of fees and expenses, to finance our redemption on July 14, 2017 of $1.041 billion aggregate principal amount of our outstanding 6.250% senior secured notes due 2018 and $1.100 billion aggregate principal amount of our outstanding 5.000% senior unsecured notes due 2019. On August 1, 2017, we assumed Escrow Corp.’s obligations with respect to the Escrow Unsecured Notes. The proceeds from the sale of the Escrow Unsecured Notes were released from escrow on August 1, 2017 and were used, after payment of fees and expenses, to finance our redemption on August 1, 2017 of $500 million aggregate principal amount of our outstanding 8.000% senior unsecured notes due 2020. On September 11, 2017, we redeemed the remaining $250 million aggregate principal amount of our outstanding 8.000% senior unsecured notes due 2020 using cash on hand. As a result of the redemption activities in the three months ended September 30, 2017 discussed above, we recorded a loss from early extinguishment of debt of $138 million in the period, primarily related to the difference between the redemption price and the par value of the notes, as well as the write-off of associated unamortized note discounts and issuance costs. All of our senior secured notes are guaranteed by certain of our wholly owned domestic hospital company subsidiaries and secured by a pledge of the capital stock and other ownership interests of those subsidiaries on either a first lien or second lien basis, as indicated in the table above. All of our senior secured notes and the related subsidiary guarantees are our and the subsidiary guarantors’ senior secured obligations. All of our senior secured notes rank equally in right of payment with all of our other senior secured indebtedness. Our senior secured notes rank senior to any subordinated indebtedness that we or such subsidiary guarantors may incur; they are effectively senior to our and such subsidiary guarantors’ existing and future unsecured indebtedness and other liabilities to the extent of the value of the collateral securing the notes and the subsidiary guarantees; they are effectively subordinated to our and such subsidiary guarantors’ obligations under our Credit Agreement to the extent of the value of the collateral securing borrowings thereunder; and they are structurally subordinated to all obligations of our non-guarantor subsidiaries. The indentures setting forth the terms of our senior secured notes contain provisions governing our ability to redeem the notes and the terms by which we may do so. At our option, we may redeem our senior secured notes, in whole or in part, at any time at a redemption price equal to 100% of the principal amount of the notes redeemed plus the make-whole premium set forth in the related indenture, together with accrued and unpaid interest thereon, if any, to the redemption date. Certain series of the senior secured notes may also be redeemed, in whole or in part, at certain redemption prices set forth in the applicable indentures, together with accrued and unpaid interest. In addition, we may be required to purchase for cash all or any part of each series of our senior secured notes upon the occurrence of a change of control (as defined in the applicable indentures) for a cash purchase price of 101% of the aggregate principal amount of the notes, plus accrued and unpaid interest. All of our senior unsecured notes are general unsecured senior debt obligations that rank equally in right of payment with all of our other unsecured senior indebtedness, but are effectively subordinated to our senior secured notes described above, the obligations of our subsidiaries and any obligations under our Credit Agreement to the extent of the value of the collateral. We may redeem any series of our senior unsecured notes, in whole or in part, at any time at a redemption price equal to 100% of the principal amount of the notes redeemed, plus a make-whole premium specified in the applicable indenture, if any, together with accrued and unpaid interest to the redemption date. Covenants Credit Agreement. Our Credit Agreement contains customary covenants for an asset-backed facility, including a minimum fixed charge coverage ratio to be met if the designated excess availability under the revolving credit facility falls below $100 million , as well as limits on debt, asset sales and prepayments of senior debt. The Credit Agreement also includes a provision, which we believe is customary in receivables-backed credit facilities, that gives our lenders the right to require that proceeds of collections of substantially all of our consolidated accounts receivable be applied directly to repay outstanding loans and other amounts that are due and payable under the Credit Agreement at any time that unused borrowing availability under the revolving credit facility is less than $100 million for three consecutive business days or if an event of default has occurred and is continuing thereunder. In that event, we would seek to re-borrow under the Credit Agreement to satisfy our operating cash requirements. Our ability to borrow under the Credit Agreement is subject to conditions that we believe are customary in revolving credit facilities, including that no events of default then exist. Senior Secured Notes. The indentures governing our senior secured notes contain covenants that, among other things, restrict our ability and the ability of our subsidiaries to incur liens, consummate asset sales, enter into sale and lease-back transactions or consolidate, merge or sell all or substantially all of our or their assets, other than in certain transactions between one or more of our wholly owned subsidiaries. These restrictions, however, are subject to a number of exceptions and qualifications. In particular, there are no restrictions on our ability or the ability of our subsidiaries to incur additional indebtedness, make restricted payments, pay dividends or make distributions in respect of capital stock, purchase or redeem capital stock, enter into transactions with affiliates or make advances to, or invest in, other entities (including unaffiliated entities). In addition, the indentures governing our senior secured notes contain a covenant that neither we nor any of our subsidiaries will incur secured debt, unless at the time of and after giving effect to the incurrence of such debt, the aggregate amount of all such secured debt (including the aggregate principal amount of senior secured notes outstanding at such time) does not exceed the amount that would cause the secured debt ratio (as defined in the indentures) to exceed 4.0 to 1.0; and indentures governing certain of our senior secured first lien notes further provide that the aggregate amount of all such debt secured by a lien on par to the lien securing the senior secured first lien notes may not exceed the amount that would cause the secured debt ratio to exceed 3.0 to 1.0. Senior Unsecured Notes. The indentures governing our senior unsecured notes contain covenants and conditions that have, among other requirements, limitations on (1) liens on “principal properties” and (2) sale and lease-back transactions with respect to principal properties. A principal property is defined in the senior unsecured notes indentures as a hospital that has an asset value on our books in excess of 5% of our consolidated net tangible assets, as defined in such indentures. The above limitations do not apply, however, to (1) debt that is not secured by principal properties or (2) debt that is secured by principal properties if the aggregate of such secured debt does not exceed 15% of our consolidated net tangible assets, as further described in the indentures. The senior unsecured notes indentures also prohibit the consolidation, merger or sale of all or substantially all assets unless no event of default would result after giving effect to such transaction. Future Maturities Future long-term debt maturities and minimum operating lease payments as of December 31, 2018 are as follows: Years Ending December 31, Later Years Total 2019 2020 2021 2022 2023 Long-term debt, including capital lease obligations $ 15,010 $ 182 $ 2,697 $ 1,958 $ 3,588 $ 1,894 $ 4,691 Long-term non-cancelable operating leases $ 932 $ 171 $ 151 $ 133 $ 113 $ 92 $ 272 Rental expense under operating leases, including short-term leases, was $326 million , $340 million and $335 million in the years ended December 31, 2018 , 2017 and 2016 , respectively. Included in rental expense for each of these periods was sublease income of $11 million , $14 million and $13 million

GUARANTEES

GUARANTEES	12 Months Ended
	Dec. 31, 2018
Guarantees [Abstract]
GUARANTEES	GUARANTEES Consistent with our policy on physician relocation and recruitment, we provide income guarantee agreements to certain physicians who agree to relocate to fill a community need in the service area of one of our hospitals and commit to remain in practice in the area for a specified period of time. Under such agreements, we are required to make payments to the physicians in excess of the amounts they earn in their practices up to the amount of the income guarantee. The income guarantee periods are typically 12 months. If a physician does not fulfill his or her commitment period to the community, which is typically three years subsequent to the guarantee period, we seek recovery of the income guarantee payments from the physician on a prorated basis. We also provide revenue collection guarantees to hospital-based physician groups providing certain services at our hospitals with terms generally ranging from one to three years. At December 31, 2018 , the maximum potential amount of future payments under our income guarantees to certain physicians who agree to relocate and revenue collection guarantees to hospital-based physician groups providing certain services at our hospitals was $166 million . We had a total liability of $123 million recorded for these guarantees included in other current liabilities at December 31, 2018 . At December 31, 2018 , we also had issued guarantees of the indebtedness and other obligations of our investees to third parties, the maximum potential amount of future payments under which was approximately $24 million . Of the total, $8 million relates to the obligations of consolidated subsidiaries, which obligations are recorded in the accompanying Consolidated Balance Sheet at December 31, 2018

EMPLOYEE BENEFIT PLANS

EMPLOYEE BENEFIT PLANS	12 Months Ended
	Dec. 31, 2018
Defined Benefit Plan [Abstract]
EMPLOYEE BENEFIT PLANS	EMPLOYEE BENEFIT PLANS Share-Based Compensation Plans In recent years, we have granted both options and restricted stock units to certain of our employees and directors pursuant to our 2008 Stock Incentive Plan, as amended. Options have an exercise price equal to the fair market value of the shares on the date of grant and generally expire 10 years from the date of grant. A restricted stock unit is a contractual right to receive one share of our common stock in the future. Typically, options and time-based restricted stock units vest one-third on each of the first three anniversary dates of the grant; however, certain special retention awards may have different vesting terms. In addition, we grant performance-based options and performance-based restricted stock units that vest subject to the achievement of specified performance goals within a specified timeframe. At December 31, 2018 , assuming outstanding performance-based restricted stock units and options for which performance has not yet been determined will achieve target performance, approximately 5.3 million shares of common stock were available under our 2008 Stock Incentive Plan for future stock option grants and other equity incentive awards, including restricted stock units ( 4.1 million shares remain available if we assume maximum performance for outstanding performance restricted stock units and options for which performance has not yet been determined). The accompanying Consolidated Statements of Operations for the years ended December 31, 2018 , 2017 and 2016 include $46 million , $59 million and $60 million , respectively, of pre-tax compensation costs related to our stock-based compensation arrangements. The table below shows certain stock option and restricted stock unit grants and other awards that comprise the stock-based compensation expense recorded in the year ended December 31, 2018 . Compensation cost is measured by the fair value of the awards on their grant dates and is recognized over the requisite service period of the awards, whether or not the awards had any intrinsic value during the period. Grant Date Awards Exercise Price Per Share Fair Value Per Share at Grant Date Stock-Based Compensation Expense for Year Ended December 31, 2018 (In Thousands) (In Millions) Stock Options: February 28, 2018 593 $ 20.60 $ 8.83 $ 2 September 29, 2017 409 $ 16.43 $ 5.63 2 March 1, 2017 877 $ 18.99 $ 8.52 1 Restricted Stock Units: June 28, 2018 51 $ 34.61 1 May 4, 2018 54 $ 23.53 1 March 29, 2018 293 $ 24.25 3 February 28, 2018 272 $ 20.60 2 March 1, 2017 404 $ 18.99 2 June 30, 2016 113 $ 27.64 1 May 31, 2016 54 $ 28.94 1 March 10, 2016 566 $ 25.50 3 February 25, 2015 1,374 $ 45.63 1 August 25, 2014 460 $ 59.90 4 Other grants 4 USPI Management Equity Plan 18 $ 46 Pursuant to the terms of our stock-based compensation plans, awards granted under the plan vest and may be exercised as determined by the human resources committee of our board of directors. In the event of a change in control, the human resources committee of our board of directors may, at its sole discretion without obtaining shareholder approval, accelerate the vesting or performance periods of the awards. Stock Options The following table summarizes stock option activity during the years ended December 31, 2018 , 2017 and 2016 : Options Weighted Average Exercise Price Per Share Aggregate Intrinsic Value Weighted Average Remaining Life (In Millions) Outstanding at December 31, 2015 1,606,842 $ 22.87 Granted — — Exercised (111,715 ) 17.88 Forfeited/Expired (59,206 ) 18.68 Outstanding at December 31, 2016 1,435,921 $ 22.87 Granted 1,396,307 18.24 Exercised (20,400 ) 4.56 Forfeited/Expired (247,006 ) 24.37 Outstanding at December 31, 2017 2,564,822 $ 20.35 Granted 635,196 21.33 Exercised (619,849 ) 18.19 Forfeited/Expired (317,426 ) 35.30 Outstanding at December 31, 2018 2,262,743 $ 19.12 $ 1 6.7 years Vested and expected to vest at December 31, 2018 2,262,743 $ 19.12 $ 1 6.7 years Exercisable at December 31, 2018 767,037 $ 17.47 $ 1 3.2 years There were 619,849 stock options exercised during the year ended December 31, 2018 with an aggregated intrinsic value of approximately $4 million , and 20,400 stock options exercised in 2017 with an aggregate intrinsic value less than $1 million . There were 635,196 performance-based stock options granted in the year ended December 31, 2018 , and 1,396,307 performance-based stock options granted in the year ended December 31, 2017 . On May 31, 2018 , we granted an aggregate of 31,184 performance-based stock options under our 2008 Stock Incentive Plan to new senior officers. The options will all vest on the third anniversary of the grant date, subject to achieving a closing stock price of at least $44.29 (a 25% premium above the grant date closing stock price of $35.43 ) for at least 20 consecutive trading days within three years of the grant date, and will expire on the tenth anniversary of the grant date. On February 28, 2018 , we granted an aggregate of 604,012 performance-based stock options under our 2008 Stock Incentive Plan to certain of our senior officers. The stock options will all vest on the third anniversary of the grant date because, in the three months ended June 30, 2018, the requirement that our stock close at a price of at least $25.75 (a 25% premium above the grant date closing stock price of $20.60 ) for at least 20 consecutive trading days within three years of the grant date was met; these options will expire on the tenth anniversary of the grant date. On March 1, 2017 , we granted 987,781 stock options to certain of our senior officers. These stock options will all vest on the third anniversary of the grant date because, in the three months ended June 30, 2018, the requirement that our stock close at a price of at least $23.74 (a 25% premium above the grant date closing stock price of $18.99 ) for at least 20 consecutive trading days within three years of the grant date was met; these options will expire on the tenth anniversary of the grant date. On September 29, 2017 , we granted our executive chairman 408,526 performance-based stock options. The options all vested on the first anniversary of the grant date because, in the three months ended June 30, 2018, the requirement that our stock close at a price of at least $20.53 (a 25% premium above the grant date closing stock price of $16.43 ) for at least 30 consecutive trading days within four years of the grant date was met; these options will expire on the fifth anniversary of the grant date. The weighted average estimated fair value of stock options we granted during the year ended December 31, 2018 and 2017 was $9.16 and $7.64 per share, respectively. These fair values were calculated based on each grant date, using a Monte Carlo simulation with the following assumptions: February 28, September 29, March 1, 2018 2017 2017 Expected volatility 46% 46% 49% Expected dividend yield 0% 0% 0% Expected life 6.2 years 3.0 years 6.2 years Expected forfeiture rate 0% 0% 0% Risk-free interest rate 2.72% 1.92% 2.15% The following table summarizes information about our outstanding stock options at December 31, 2018 : Options Outstanding Options Exercisable Range of Exercise Prices Number of Options Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number of Options Weighted Average Exercise Price $0.00 to $4.569 82,409 0.2 years $ 4.56 82,409 $ 4.56 $4.57 to $19.759 1,285,795 6.7 years $ 18.18 413,960 $ 16.46 $19.76 to $35.430 894,539 7.4 years $ 21.83 270,668 $ 22.94 2,262,743 6.7 years $ 19.12 767,037 $ 17.47 As of December 31, 2018 , 71.5% of all our outstanding options were held by current employees and 28.5% were held by former employees. Of our outstanding options, 21.7% were in-the-money, that is, they had exercise price less than the $17.14 market price of our common stock on December 31, 2018 , and 78.3% were out-of-the-money, that is, they had an exercise price of more than $17.14 as shown in the table below: In-the-Money Options Out-of-the-Money Options All Options Outstanding % of Total Outstanding % of Total Outstanding % of Total Current employees 469,849 95.7 % 1,147,105 64.7 % 1,616,954 71.5 % Former employees 21,086 4.3 % 624,703 35.3 % 645,789 28.5 % Totals 490,935 100.0 % 1,771,808 100.0 % 2,262,743 100.0 % % of all outstanding options 21.7 % 78.3 % 100.0 % Restricted Stock Units The following table summarizes restricted stock unit activity during the years ended December 31, 2018 , 2017 and 2016 : Restricted Stock Units Weighted Average Grant Date Fair Value Per Unit Unvested at December 31, 2015 3,627,232 $ 44.69 Granted 1,626,329 30.05 Vested (1,644,616 ) 42.95 Forfeited (434,412 ) 38.59 Unvested at December 31, 2016 3,174,533 $ 38.75 Granted 714,018 18.25 Vested (1,397,953 ) 35.50 Forfeited (236,610 ) 32.13 Unvested at December 31, 2017 2,253,988 $ 35.20 Granted 765,184 24.74 Vested (995,331 ) 32.63 Forfeited (139,711 ) 36.01 Unvested at December 31, 2018 1,884,130 $ 32.25 In the year ended December 31, 2018 , we granted 765,184 restricted stock units, of which 288,325 will vest and be settled ratably over a three-year period from the grant date, 339,806 will vest and be settled ratably over two-year period from the grant date, and 60,963 will vest and be settled on the third anniversary of the grant date. In addition, in May 2018, we made an annual grant of 54,198 restricted stock units to our non-employee directors for the 2018-2019 board service year, which units vested immediately and will settle in shares of our common stock on the third anniversary of the date of the grant. Because the Board of Directors appointed two new members in May 2018, we made initial grants totaling 3,670 restricted stock units to these directors, as well as prorated annual grants totaling 12,154 restricted stock units. Both the initial grants and the annual grants vested immediately; however, the initial grants will not settle until the directors’ separation from the Board, while the annual grants settle on the third anniversary of the grant date. In addition, we granted 6,068 performance-based restricted stock units to certain of our senior officers; the vesting of these restricted stock units is contingent on our achievement of specified three-year performance goals for the years 2018 to 2020. Provided the goals are achieved, the performance-based restricted stock units will vest and settle on the third anniversary of the grant date. The actual number of performance-based restricted stock units that could vest will range from 0% to 200% of the 6,068 units granted, depending on our level of achievement with respect to the performance goals. In the year ended December 31, 2017 , we granted 714,018 restricted stock units of which 518,229 will vest and be settled ratably over a three -year period from the grant date. In addition, in May 2017, we made an annual grant of 145,179 restricted stock units to our non-employee directors for the 2017-2018 board service year, which units vested immediately and will settle in shares of our common stock on the third anniversary of the date of the grant. Because the Board of Directors appointed three new members, one in October 2017 and two in November 2017, we made initial grants totaling 13,772 restricted stock units to these directors, as well as prorated annual grants totaling 23,935 restricted stock units. Both the initial grants and the annual grants vested immediately; however, the initial grants will not settle until the directors’ separation from the Board, while the annual grants settle on the third anniversary of the grant date. In addition, we granted 12,903 performance-based restricted stock units to certain of our senior officers; the vesting of these restricted stock units is contingent on our achievement of specified three-year performance goals for the years 2017 to 2019. Provided the goals are achieved, the performance-based restricted stock units will vest and settle on the third anniversary of the grant date. The actual number of performance-based restricted stock units that could vest will range from 0% to 200% of the 12,903 units granted, depending on our level of achievement with respect to the performance goals. As of December 31, 2018 , there were $18 million of total unrecognized compensation costs related to restricted stock units. These costs are expected to be recognized over a weighted average period of 1.5 years. USPI Management Equity Plan USPI maintains a separate management equity plan whereby it has granted non-qualified options to purchase nonvoting shares of USPI’s outstanding common stock to eligible plan participants, allowing the recipient to participate in the incremental growth in the value of USPI from the applicable grant date. The total pool of options consists of approximately 10% of USPI’s fully diluted outstanding common stock. Options have an exercise price equal to the estimated fair market value of USPI’s common stock on the date of grant, and expire upon the earlier of seven years from the date of grant or July 2022 . The option awards have been structured such that they have a three or four year vesting period in which half of the award vests in equal pro-rata amounts over the applicable vesting period and the remaining half vests at the end of the applicable three or four year period. Any unvested awards are forfeited upon the recipient’s termination of service with USPI and vested options must be exercised within 90 days of termination. Once an award is exercised, the recipient must hold the underlying shares for at least six months plus one day and then is eligible to sell the underlying shares to USPI at their estimated fair market value. USPI is only required to purchase any of these eligible nonvoting common shares during a three months window in the third quarter of each calendar year. In addition, at any time after the earlier of (i) July 2022 , or (ii) one year and seven days after all of the options have become exercisable, USPI has the right, but not the obligation, to purchase from each holder of the outstanding shares of nonvoting common stock all or a portion of such shares at their estimated fair market value, provided the shares have been held for the requisite holding period. Payment for USPI’s purchase of any eligible nonvoting common shares may be made in cash or in shares of Tenet’s common stock. The accompanying Consolidated Statement of Operations for the years ended December 31, 2018 , 2017 and 2016 includes $18 million , $13 million and $10 million , respectively, of pre-tax compensation costs related to USPI’s management equity plan. Employee Stock Purchase Plan We have an employee stock purchase plan under which we are currently authorized to issue up to 5,062,500 shares of common stock to our eligible employees. As of December 31, 2018 , there were approximately 3.2 million shares available for issuance under our employee stock purchase plan. Under the terms of the plan, eligible employees may elect to have between 1% and 10% of their base earnings withheld each quarter to purchase shares of our common stock. Shares are purchased at a price equal to 95% of the closing price on the last day of the quarter. The plan requires a one-year holding period for all shares issued. The holding period does not apply upon termination of employment. Under the plan, no individual may purchase, in any year, shares with a fair market value in excess of $25,000 . The plan is currently not considered to be compensatory. We sold the following numbers of shares under our employee stock purchase plan in the years ended December 31, 2018 , 2017 and 2016 : Years Ended December 31, 2018 2017 2016 Number of shares 228,045 395,957 217,184 Weighted average price $ 22.96 $ 17.28 $ 17.21 Employee Retirement Plans Substantially all of our employees, upon qualification, are eligible to participate in one of our defined contribution 401(k) plans. Under the plans, employees may contribute a portion of their eligible compensation, and we match such contributions annually up to a maximum percentage for participants actively employed, as defined by the plan documents. Employer matching contributions will vary by plan. Plan expenses, primarily related to our contributions to the plans, were $99 million , $128 million and $116 million for the years ended December 31, 2018 , 2017 and 2016 , respectively. Such amounts are reflected in salaries, wages and benefits in the accompanying Consolidated Statements of Operations. We maintain three frozen non-qualified defined benefit pension plans (“SERPs”) that provide supplemental retirement benefits to certain of our current and former executives. These plans are not funded, and plan obligations for these plans are paid from our working capital. Pension benefits are generally based on years of service and compensation. Upon completing the acquisition of Vanguard Health Systems, Inc. on October 1, 2013, we assumed a frozen qualified defined benefit plan (“DMC Pension Plan”) covering substantially all of the employees of our Detroit market that were hired prior to June 1, 2003. The benefits paid under the DMC Pension Plan are primarily based on years of service and final average earnings. During the years ended December 31, 2018 and 2017 , the Society of Actuaries issued new mortality improvement scales (MP-2018 and MP‑2017, respectively), which we incorporated into the estimates of our defined benefit plan obligations at December 31, 2018 and 2017 . These changes to our mortality assumptions decreased our projected benefit obligations as of December 31, 2018 and 2017 by approximately $4 million and $10 million , respectively. The following tables summarize the balance sheet impact, as well as the benefit obligations, funded status and rate assumptions associated with the SERPs and the DMC Pension Plan based on actuarial valuations prepared as of December 31, 2018 and 2017 : December 31, 2018 2017 Reconciliation of funded status of plans and the amounts included in the Consolidated Balance Sheets: Projected benefit obligations (1) Beginning obligations $ (1,455 ) $ (1,475 ) Service cost (2 ) (2 ) Interest cost (56 ) (62 ) Actuarial gain (loss) 90 (31 ) Benefits paid 122 120 Special termination benefit costs — (5 ) Ending obligations (1,301 ) (1,455 ) Fair value of plans assets Beginning plan assets 850 786 Gain (loss) on plan assets (65 ) 122 Employer contribution 47 43 Benefits paid (101 ) (101 ) Ending plan assets 731 850 Funded status of plans $ (570 ) $ (605 ) Amounts recognized in the Consolidated Balance Sheets consist of: Other current liability $ (49 ) $ (69 ) Other long-term liability $ (521 ) $ (536 ) Accumulated other comprehensive loss $ 281 $ 266 SERP Assumptions: Discount rate 4.50 % 3.75 % Compensation increase rate 3.00 % 3.00 % Measurement date December 31, 2018 December 31, 2017 DMC Pension Plan Assumptions: Discount rate 4.62 % 4.00 % Compensation increase rate Frozen Frozen Measurement date December 31, 2018 December 31, 2017 (1) The accumulated benefit obligation at December 31, 2018 and 2017 was approximately $1.299 billion and $1.448 billion , respectively. The components of net periodic benefit costs and related assumptions are as follows: Years Ended December 31, 2018 2017 2016 Service costs $ 2 $ 2 $ 2 Interest costs 56 62 69 Expected return on plan assets (54 ) (50 ) (51 ) Amortization of net actuarial loss 14 14 12 Net periodic benefit cost $ 18 $ 28 $ 32 SERP Assumptions: Discount rate 3.75 % 4.25 % 4.75 % Long-term rate of return on assets n/a n/a n/a Compensation increase rate 3.00 % 3.00 % 3.00 % Measurement date January 1, 2018 January 1, 2017 January 1, 2016 Census date January 1, 2018 January 1, 2017 January 1, 2016 DMC Pension Plan Assumptions: Discount rate 4.00 % 4.42 % 4.67 % Long-term rate of return on assets 6.50 % 6.50 % 6.50 % Compensation increase rate Frozen Frozen Frozen Measurement date January 1, 2018 January 1, 2017 January 1, 2016 Census date January 1, 2018 January 1, 2017 January 1, 2016 Net periodic benefit costs for the current year are based on assumptions determined at the valuation date of the prior year for the SERPs and the DMC Pension Plan. As a result of the adoption of ASU 2017-07 discussed in Note 1, we recognized service costs in salaries, wages and benefits expense, and recognized other components of net periodic benefit cost in other non-operating expense, net, in the accompanying Consolidated Statements of Operations. We recorded gain (loss) adjustments of $(15) million , $56 million and $(61) million in other comprehensive income (loss) in the years ended December 31, 2018 , 2017 and 2016 , respectively, to recognize changes in the funded status of our SERPs and the DMC Pension Plan. Changes in the funded status are recorded as a direct increase or decrease to shareholders’ equity through accumulated other comprehensive loss. Net actuarial gains (losses) of $(29) million , $42 million and $(73) million were recognized during the years ended December 31, 2018 , 2017 and 2016 , respectively, and the amortization of net actuarial loss of $14 million , $14 million and $12 million for the years ended December 31, 2018 , 2017 and 2016 , respectively, were recognized in other comprehensive income (loss). Cumulative net actuarial losses of $281 million , $266 million and $322 million as of December 31, 2018 , 2017 and 2016 , respectively, and unrecognized prior service costs of less than $1 million as of each of the years ended December 31, 2018 , 2017 and 2016 have not yet been recognized as components of net periodic benefit cost. To develop the expected long-term rate of return on plan assets assumption, the DMC Pension Plan considers the current level of expected returns on risk-free investments (primarily government bonds), the historical level of risk premium associated with the other asset classes in which the portfolio is invested and the expectations for future returns on each asset class. The expected return for each asset class is then weighted based on the target asset allocation to develop the expected long-term rate of return on assets assumption for the portfolio. The weighted-average asset allocations by asset category as of December 31, 2018 , were as follows: Asset Category Target Actual Cash and cash equivalents 2 % 2 % U.S. government obligations — % 2 % Equity securities 64 % 65 % Debt securities 34 % 31 % Alternative investments 1 % 1 % The DMC Pension Plan assets are invested in separately managed portfolios using investment management firms. The objective for all asset categories is to maximize total return without assuming undue risk exposure. The DMC Pension Plan maintains a well-diversified asset allocation that best meets these objectives. The DMC Pension Plan assets are largely comprised of equity securities, which include companies with various market capitalization sizes in addition to international and convertible securities. Cash and cash equivalents are comprised of money market funds. Debt securities include domestic and foreign government obligations, corporate bonds, and mortgage-backed securities. Under the investment policy of the DMC Pension Plan, investments in derivative securities are not permitted for the sole purpose of speculating on the direction of market interest rates. Included in this prohibition are leveraging, shorting, swaps, futures, options, forwards and similar strategies. In each investment account, the DMC Pension Plan investment managers are responsible for monitoring and reacting to economic indicators, such as gross domestic product, consumer price index and U.S. monetary policy that may affect the performance of their account. The performance of all managers and the aggregate asset allocation are formally reviewed on a quarterly basis, with a rebalancing of the asset allocation occurring at least once per year. The current asset allocation objective is to maintain a certain percentage with each class allowing for a 10% deviation from the target. The following tables summarize the DMC Pension Plan assets measured at fair value on a recurring basis as of December 31, 2018 and 2017 , aggregated by the level in the fair value hierarchy within which those measurements are determined. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities. We consider a security that trades at least weekly to have an active market. Fair values determined by Level 2 inputs utilize data points that are observable, such as quoted prices for similar assets, interest rates and yield curves. Fair values determined by Level 3 inputs are unobservable data points for the asset or liability, and include situations where there is little, if any, market activity for the asset or liability. December 31, 2018 Level 1 Level 2 Level 3 Cash and cash equivalents $ 33 $ 33 $ — $ — U.S. government obligations 9 9 — — Equity securities 423 423 — — Fixed income funds 262 262 — — Futures contracts 4 4 — — $ 731 $ 731 $ — $ — December 31, 2017 Level 1 Level 2 Level 3 Cash and cash equivalents $ 49 $ 49 $ — $ — U.S. government obligations 5 5 — — Equity securities 488 488 — — Fixed income funds 308 308 — — $ 850 $ 850 $ — $ — The following table presents the estimated future benefit payments to be made from the SERPs and the DMC Pension Plan, a portion of which will be funded from plan assets, for the next five years and in the aggregate for the five years thereafter: Years Ending December 31, Five Years Total 2019 2020 2021 2022 2023 Thereafter Estimated benefit payments $ 897 $ 86 $ 89 $ 90 $ 91 $ 91 $ 450 The SERP and DMC Pension Plan obligations of $570 million at December 31, 2018 are classified in the accompanying Consolidated Balance Sheet as an other current liability ( $49 million ) and defined benefit plan obligations ( $521 million ) based on an estimate of the expected payment patterns. We expect to make total contributions to the plans of approximately $49 million for the year ending December 31, 2019

PROPERTY AND EQUIPMENT

PROPERTY AND EQUIPMENT	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
PROPERTY AND EQUIPMENT	PROPERTY AND EQUIPMENT The principal components of property and equipment are shown in the table below: December 31, 2018 2017 Land $ 613 $ 602 Buildings and improvements 6,920 6,837 Construction in progress 199 109 Equipment 4,482 4,221 12,214 11,769 Accumulated depreciation and amortization (5,221 ) (4,739 ) Net property and equipment $ 6,993 $ 7,030

GOODWILL AND OTHER INTANGIBLE A

GOODWILL AND OTHER INTANGIBLE ASSETS	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND OTHER INTANGIBLE ASSETS	GOODWILL AND OTHER INTANGIBLE ASSETS The following table provides information on changes in the carrying amount of goodwill, which is included in the accompanying Consolidated Balance Sheets as of 2018 and 2017 : 2018 2017 Hospital Operations and other As of January 1: Goodwill $ 5,406 $ 5,803 Accumulated impairment losses (2,430 ) (2,430 ) Total 2,976 3,373 Goodwill acquired during the year and purchase price allocation adjustments 1 5 Goodwill related to assets held for sale and disposed or deconsolidated facilities 3 (402 ) Total $ 2,980 $ 2,976 As of December 31: Goodwill $ 5,410 $ 5,406 Accumulated impairment losses (2,430 ) (2,430 ) Total $ 2,980 $ 2,976 2018 2017 Ambulatory Care As of January 1: Goodwill $ 3,437 $ 3,447 Accumulated impairment losses — — Total 3,437 3,447 Goodwill acquired during the year and purchase price allocation adjustments 219 86 Goodwill related to assets held for sale and disposed or deconsolidated facilities 40 (103 ) Impact of foreign currency translation — 7 Total $ 3,696 $ 3,437 As of December 31: Goodwill $ 3,696 $ 3,437 Accumulated impairment losses — — Total $ 3,696 $ 3,437 2018 2017 Conifer As of January 1: Goodwill $ 605 $ 605 Accumulated impairment losses — — Total 605 605 Goodwill acquired during the year and purchase price allocation adjustments — — Total $ 605 $ 605 As of December 31: Goodwill $ 605 $ 605 Accumulated impairment losses — — Total $ 605 $ 605 The following table provides information regarding other intangible assets, which are included in the accompanying Consolidated Balance Sheets as of 2018 and 2017 : Gross Carrying Amount Accumulated Amortization Net Book Value At December 31, 2018: Capitalized software costs $ 1,667 $ (858 ) $ 809 Trade names 102 — 102 Contracts 871 (76 ) 795 Other 104 (79 ) 25 Total $ 2,744 $ (1,013 ) $ 1,731 At December 31, 2017: Capitalized software costs $ 1,582 $ (754 ) $ 828 Trade Names 102 — 102 Contracts 859 (60 ) 799 Other 106 (69 ) 37 Total $ 2,649 $ (883 ) $ 1,766 Estimated future amortization of intangibles with finite useful lives as of December 31, 2018 is as follows: Total Years Ending December 31, Later Years 2019 2020 2021 2022 2023 Amortization of intangible assets $ 1,053 $ 147 $ 131 $ 112 $ 99 $ 85 $ 479 We recognized amortization expense of $185 million , $172 million and $152 million in the accompanying Consolidated Statements of Operations for the years ended December 31, 2018 , 2017 and 2016

INVESTMENTS AND OTHER ASSETS

INVESTMENTS AND OTHER ASSETS	12 Months Ended
	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
INVESTMENTS AND OTHER ASSETS	INVESTMENTS AND OTHER ASSETS The principal components of investments and other assets in the accompanying Consolidated Balance Sheets are as follows: December 31, 2018 2017 Marketable securities $ 40 $ 56 Equity investments in unconsolidated healthcare entities 956 958 Total investments 996 1,014 Cash surrender value of life insurance policies 30 32 Long-term deposits 44 37 California provider fee program receivables 231 266 Land held for expansion, other long-term receivables and other assets 155 194 Investments and other assets $ 1,456 $ 1,543

ACCUMULATED OTHER COMPREHENSIVE

ACCUMULATED OTHER COMPREHENSIVE LOSS	12 Months Ended
	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
ACCUMULATED OTHER COMPREHENSIVE LOSS	ACCUMULATED OTHER COMPREHENSIVE LOSS Our accumulated other comprehensive loss is comprised of the following: December 31, 2018 2017 Adjustments for defined benefit plans $ (223 ) $ (170 ) Foreign currency translation adjustments — (38 ) Unrealized gains on investments $ — $ 4 Accumulated other comprehensive loss $ (223 ) $ (204 ) The tax benefits allocated to the adjustments for our defined benefit plans and foreign currency translation adjustments were approximately $3 million and $3 million , respectively, for the year ended December 31, 2018 , and the tax expense allocated to the adjustments for our defined benefit plans, foreign currency translation adjustments and unrealized gains on investments were approximately $15 million , $5 million , and $3 million , respectively, for the year ended December 31, 2017 . As discussed in Note 1, we recorded cumulative effect adjustments of $36 million and $7 million upon the adoptions of ASU 2018-02 and ASU 2016-01

NET OPERATING REVENUES

NET OPERATING REVENUES	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
NET OPERATING REVENUES	CONTRACT BALANCES Hospital Operations and Other Segment Under the provisions of ASU 2014-09, which we adopted effective January 1, 2018, amounts related to services provided to patients for which we have not billed and that do not meet the conditions of unconditional right to payment at the end of the reporting period are contract assets. For our Hospital Operations and other segment, our contract assets consist primarily of services that we have provided to patients who are still receiving inpatient care in our facilities at the end of the reporting period. Our Hospital Operations and other segment’s contract assets are included in other current assets in the accompanying Consolidated Balance Sheet at December 31, 2018. The opening and closing balances of contract assets for our Hospital Operations and other segment are as follows: 2018 2017 January 1, $ 171 $ — December 31, 169 — Increase/(decrease) $ (2 ) $ — The increase in the contract asset balances from the year ended December 31, 2018 compared to the year ended December 31, 2017 is due to the implementation of ASU 2014-09 effective January 1, 2018 using a modified retrospective method of application. Prior to January 1, 2018, amounts related to services provided to patients for which we had not billed were included in accounts receivable, less allowance for doubtful accounts, in our consolidated balance sheets. Approximately 89% of our Hospital Operations and other segment’s contract assets meet the conditions for unconditional right to payment and are reclassified to patient receivables within 90 days. Conifer Segment Conifer enters into contracts with customers to sell revenue cycle management and other services, such as value-based care, consulting and project services. The payment terms and conditions in our customer contracts vary. In some cases, customers are invoiced in advance and (for other than fixed-price fee arrangements) a true-up to the actual fee is included on a subsequent invoice. In other cases, payment is due in arrears. In addition, some contracts contain performance incentives, penalties and other forms of variable consideration. When the timing of Conifer’s delivery of services is different from the timing of payments made by the customers, Conifer recognizes either unbilled revenue (performance precedes contractual right to invoice the customer) or deferred revenue (customer payment precedes Conifer service performance). In the following table, customers that prepay prior to obtaining control/benefit of the service are represented by deferred contract revenue until the performance obligations are satisfied. Unbilled revenue represents arrangements in which Conifer has provided services to and the customer has obtained control/benefit of services prior to the contractual invoice date. Contracts with payment in arrears are recognized as receivables in the month the service is performed. The opening and closing balances of Conifer’s receivables, contract asset, and current and long-term contract liabilities are as follows: Contract Liability- Contract Liability- Contract Asset- Current Long-Term Receivables Unbilled Revenue Deferred Revenue Deferred Revenue January 1, 2018 $ 89 $ 10 $ 80 $ 21 December 31, 2018 42 11 61 20 Increase/(decrease) $ (47 ) $ 1 $ (19 ) $ (1 ) January 1, 2017 $ 67 $ 8 $ 76 $ 26 December 31, 2017 89 10 80 21 Increase/(decrease) $ 22 $ 2 $ 4 $ (5 ) The difference between the opening and closing balances of Conifer’s contract assets and contract liabilities are primarily related to prepayments for those customers who are billed in advance, changes in estimates related to metric-based services, and up-front integration services that are typically not distinct and are, therefore, recognized over the performance obligation period to which they relate. Our Conifer segment’s receivables and contract assets are reported as part of other current assets in our accompanying Consolidated Balance Sheets, and our Conifer segment’s current and long-term contract liabilities are reported as part of other current liabilities and other long-term liabilities, respectively, in our accompanying Consolidated Balance Sheets. The amount of revenue Conifer recognized in the years ended December 31, 2018 and 2017 that was included in the opening current deferred revenue liability was $72 million and $73 million , respectively. This revenue consists primarily of prepayments for those customers who are billed in advance, changes in estimates related to metric-based services, and up-front integration services that are recognized over the services period. Contract Costs We have elected to apply the practical expedient provided by ASC 340-40-25-4 and expense as incurred the incremental customer contract acquisition costs for contracts in which the amortization period of the asset that we otherwise would have recognized is one year or less. However, incremental costs incurred to obtain and fulfill customer contracts for which the amortization period of the asset that we otherwise would have recognized is longer than one year, which consist primarily of Conifer deferred contract setup costs, are capitalized and amortized on a straight-line basis over the lesser of their estimated useful lives or the term of the related contract. During the years ended December 31, 2018 , 2017 and 2016 , we recognized amortization expense of $11 million , $10 million and 7 million , respectively. At December 31, 2018 and 2017 , the unamortized customer contract costs were $28 million and $35 million Net operating revenues for our Hospital Operations and other and Ambulatory Care segments primarily consist of net patient service revenues, principally for patients covered by Medicare, Medicaid, managed care and other health plans, as well as certain uninsured patients under our Compact and other uninsured discount and charity programs. Net operating revenues for our Conifer segment primarily consist of revenues from providing revenue cycle management services to healthcare systems, as well as individual hospitals, physician practices, self-insured organizations, health plans and other entities. The table below shows our sources of net operating revenues less provision for doubtful accounts and implicit price concessions from continuing operations: Years Ended December 31, 2018 2017 2016 Hospital Operations and other: Net patient service revenues from hospitals and related Medicare $ 2,882 $ 3,243 $ 3,386 Medicaid 1,294 1,304 1,346 Managed care 9,213 9,583 9,728 Self-pay 96 91 63 Indemnity and other 596 608 604 Total 14,081 14,829 15,127 Physician practices revenues 1,097 1,209 1,201 Health plans 14 110 482 Revenue from other sources 93 112 94 Hospital Operations and other total prior to 15,285 16,260 16,904 Ambulatory Care 2,085 1,940 1,797 Conifer 1,533 1,597 1,571 Inter-segment eliminations (590 ) (618 ) (651 ) Net operating revenues $ 18,313 $ 19,179 $ 19,621 Adjustments for prior-year cost reports and related valuation allowances, principally related to Medicare and Medicaid, increased revenues in the years ended December 31, 2018 , 2017 and 2016 by $24 million , $35 million and $54 million , respectively. Estimated cost report settlements and valuation allowances are included in accounts receivable in the accompanying Consolidated Balance Sheets (see Note 3). We believe that we have made adequate provision for any adjustments that may result from final determination of amounts earned under all the above arrangements with Medicare and Medicaid. The table below shows the composition of net operating revenues less provision for doubtful accounts and implicit price concessions for our Ambulatory Care segment: Years Ended December 31, 2018 2017 2016 Net patient service revenues $ 1,965 $ 1,816 $ 1,684 Management fees 92 93 89 Revenue from other sources 28 31 24 Net operating revenues $ 2,085 $ 1,940 $ 1,797 The table below shows the composition of net operating revenues for our Conifer segment: Years Ended December 31, 2018 2017 2016 Revenue cycle services – Tenet $ 568 $ 583 $ 596 Revenue cycle services – other customers 855 891 839 Other services – Tenet 22 35 55 Other services – other customers 88 88 81 Total revenues from client contracts $ 1,533 $ 1,597 $ 1,571 Other services represent 7% of Conifer’s revenue and include value-based care, consulting and project services. Performance Obligations The following table includes Conifer’s revenue that is expected to be recognized in the future related to performance obligations that are unsatisfied, or partially unsatisfied, at the end of the reporting period. The amounts in the table primarily consist of revenue cycle management fixed fees, which are typically recognized ratably as the performance obligation is satisfied. The estimated revenue does not include volume or contingency based contracts, performance incentives, penalties or other variable consideration that is considered constrained. Conifer’s contract with Catholic Health Initiatives (“CHI”), a minority interest owner of Conifer Health Solutions, LLC, represents the majority of the fixed-fee revenue related to remaining performance obligations. Conifer’s contract term with CHI ends in 2032. Years Ending December 31, Later Years Total 2019 2020 2021 2022 2023 Performance obligations $ 7,736 $ 585 $ 584 $ 581 $ 581 $ 581 $ 4,824

PROPERTY AND PROFESSIONAL AND G

PROPERTY AND PROFESSIONAL AND GENERAL LIABILITY INSURANCE	12 Months Ended
	Dec. 31, 2018
Property and Professional and General Liablity Insurance [Abstract]
PROPERTY AND PROFESSIONAL AND GENERAL LIABILITY INSURANCE	PROPERTY AND PROFESSIONAL AND GENERAL LIABILITY INSURANCE Property Insurance We have property, business interruption and related insurance coverage to mitigate the financial impact of catastrophic events or perils that is subject to deductible provisions based on the terms of the policies. These policies are on an occurrence basis. For the policy period April 1, 2018 through March 31, 2019, we have coverage totaling $850 million per occurrence, after deductibles and exclusions, with annual aggregate sub-limits of $100 million for floods, $200 million for earthquakes and a per-occurrence sub-limit of $200 million for named windstorms with no annual aggregate. With respect to fires and other perils, excluding floods, earthquakes and named windstorms, the total $850 million limit of coverage per occurrence applies. Deductibles are 5% of insured values up to a maximum of $25 million for California earthquakes, floods and named windstorms, and 2% of insured values for New Madrid fault earthquakes, with a maximum per claim deductible of $25 million . Floods and certain other covered losses, including fires and other perils, have a minimum deductible of $1 million . Professional and General Liability Reserves We are self-insured for the majority of our professional and general liability claims and purchase insurance from third-parties to cover catastrophic claims. At December 31, 2018 and 2017 , the aggregate current and long-term professional and general liability reserves in the accompanying Consolidated Balance Sheets were $882 million and $854 million , respectively. These reserves include the reserves recorded by our captive insurance subsidiaries and our self-insured retention reserves recorded based on modeled estimates for the portion of our professional and general liability risks, including incurred but not reported claims, for which we do not have insurance coverage. We estimated the reserves for losses and related expenses using expected loss-reporting patterns discounted to their present value under a risk-free rate approach using a Federal Reserve seven-year maturity rate of 2.59% , 2.33% and 2.25% at December 31, 2018 , 2017 and 2016 , respectively. If the aggregate limit of any of our professional and general liability policies is exhausted, in whole or in part, it could deplete or reduce the limits available to pay any other material claims applicable to that policy period. Included in other operating expenses, net, in the accompanying Consolidated Statements of Operations is malpractice expense of $388 million , $303 million and $281 million for the years ended December 31, 2018 , 2017 and 2016

CLAIMS AND LAWSUITS

CLAIMS AND LAWSUITS	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
CLAIMS AND LAWSUITS	CLAIMS AND LAWSUITS We operate in a highly regulated and litigious industry. Healthcare companies are subject to numerous investigations by various governmental agencies. Further, private parties have the right to bring qui tam or “whistleblower” lawsuits against companies that allegedly submit false claims for payments to, or improperly retain overpayments from, the government and, in some states, private payers. We and our subsidiaries have received inquiries in recent years from government agencies, and we may receive similar inquiries in future periods. We are also subject to class action lawsuits, employment-related claims and other legal actions in the ordinary course of business. Some of these actions may involve large demands, as well as substantial defense costs. We cannot predict the outcome of current or future legal actions against us or the effect that judgments or settlements in such matters may have on us. We are also subject to a non-prosecution agreement (“NPA”). If we fail to comply with this agreement, we could be subject to criminal prosecution, substantial penalties and exclusion from participation in federal healthcare programs, any of which could adversely impact our business, financial condition, results of operations or cash flows. We record accruals for estimated losses relating to claims and lawsuits when available information indicates that a loss is probable and we can reasonably estimate the amount of the loss or a range of loss. Significant judgment is required in both the determination of the probability of a loss and the determination as to whether a loss is reasonably estimable. These determinations are updated at least quarterly and are adjusted to reflect the effects of negotiations, settlements, rulings, advice of legal counsel and technical experts, and other information and events pertaining to a particular matter, but are subject to significant uncertainty regarding numerous factors that could affect the ultimate loss levels. If a loss on a material matter is reasonably possible and estimable, we disclose an estimate of the loss or a range of loss. In cases where we have not disclosed an estimate, we have concluded that the loss is either not reasonably possible or the loss, or a range of loss, is not reasonably estimable, based on available information. Given the inherent uncertainties involved in these matters, especially those involving governmental agencies, and the indeterminate damages sought in some of these matters, there is significant uncertainty as to the ultimate liability we may incur from these matters, and an adverse outcome in one or more of these matters could be material to our results of operations or cash flows for any particular reporting period. Shareholder Derivative Litigation In January 2017, the Dallas County District Court consolidated two previously disclosed shareholder derivative lawsuits filed on behalf of the Company by purported shareholders of the Company’s common stock against current and former officers and directors into a single matter captioned In re Tenet Healthcare Corporation Shareholder Derivative Litigation . The plaintiffs filed a consolidated shareholder derivative petition in February 2017. The consolidated shareholder derivative petition alleged that false or misleading statements or omissions concerning the Company’s financial performance and compliance policies, specifically with respect to the previously disclosed civil qui tam litigation and parallel criminal investigation of the Company and certain of its subsidiaries (together, the “Clinica de la Mama matters”), caused the price of the Company’s common stock to be artificially inflated. In addition, the plaintiffs alleged that the defendants violated GAAP by failing to disclose an estimate of the possible loss or a range of loss related to the Clinica de la Mama matters. The plaintiffs claimed that they did not make demand on the Company’s board of directors to bring the lawsuit because such a demand would have been futile. In May 2018, the judge in the consolidated shareholder derivative litigation entered an order lifting the previous year-long stay of the matter and, in July 2018, the defendants filed pleadings seeking dismissal of the lawsuit. In October 2018, the judge granted defendants’ motion to dismiss, but also agreed to give the plaintiffs 30 days to replead their complaint. On January 30, 2019, the court issued a final judgment and order of dismissal after the plaintiffs elected not to replead. The plaintiffs have indicated that they will appeal the court’s ruling that dismissal was appropriate because they failed to adequately plead that a pre-suit demand on Tenet’s Board of Directors, a precondition to their action, should be excused as futile. The plaintiffs have until March 1, 2019 to file an appeal. If necessary, the defendants intend to continue to vigorously contest the plaintiffs’ allegations in this matter. Antitrust Class Action Lawsuit Filed by Registered Nurses in San Antonio In Maderazo, et al. v. VHS San Antonio Partners, L.P. d/b/a Baptist Health Systems, et al. , filed in June 2006 in the U.S. District Court for the Western District of Texas, a purported class of registered nurses employed by three unaffiliated San Antonio-area hospital systems allege those hospital systems, including our Baptist Health System, and other unidentified San Antonio regional hospitals violated Section §1 of the federal Sherman Act by conspiring to depress nurses’ compensation and exchanging compensation-related information among themselves in a manner that reduced competition and suppressed the wages paid to such nurses. The suit seeks unspecified damages (subject to trebling under federal law), interest, costs and attorneys’ fees. On January 23, 2019, the district court issued an opinion denying the plaintiffs’ motion for class certification. On February 5, 2019, the plaintiffs appealed the district court’s decision to the U.S. Court of Appeals for the Fifth Circuit. We will continue to vigorously defend ourselves against the plaintiffs’ allegations. Government Investigation of Detroit Medical Center Detroit Medical Center (“DMC”) is subject to an ongoing investigation by the U.S. Attorney’s Office for the Eastern District of Michigan and the U.S. Department of Justice (“DOJ”) for potential violations of the Stark law, the Medicare and Medicaid anti-kickback and anti-fraud and abuse amendments codified under Section 1128B(b) of the Social Security Act (the “Anti-kickback Statute”), and the federal False Claims Act (“FCA”) related to DMC’s employment of nurse practitioners and physician assistants (“Mid-Level Practitioners”) from 2006 through 2017. As previously disclosed, a media report was published in August 2017 alleging that 14 Mid-Level Practitioners were terminated by DMC earlier in 2017 due to compliance concerns. We are cooperating with the investigation and continue to produce documents on a schedule agreed upon with the DOJ. Because the government’s review is in its preliminary stages, we are unable to determine the potential exposure, if any, at this time. Oklahoma Surgical Hospital Qui Tam Action In September 2016, a relator filed a qui tam lawsuit under seal in the Western District of Oklahoma against, among other parties, (i) Oklahoma Center for Orthopaedic & Multispecialty Surgery (“OCOM”), a surgical hospital jointly owned by USPI, a healthcare system partner and physicians, (ii) Southwest Orthopaedic Specialists (“SOS”), an independent physician practice group, (iii) Tenet, and (iv) other related entities and individuals. The complaint alleges various violations of the FCA, the Anti-kickback Statute, the Stark law and the Oklahoma Medicaid False Claims Act. In May 2018, Tenet and its affiliates learned that they were parties to the suit when the court unsealed the complaint and the DOJ declined to intervene with respect to the issues involving Tenet, USPI, OCOM and individually named employees. In June 2018, the relator filed an amended complaint more fully describing the claims and adding additional defendants. Tenet, USPI, OCOM and individually named employees filed motions to dismiss the case in October 2018, but the court has not yet ruled on the motions. On February 11, 2019, the court granted a motion brought by the SOS defendants and the relator for a four-month stay so that those parties could continue conferring regarding the issues and claims in the case. Pursuant to the obligations under our NPA, we reported the unsealed qui tam action to the DOJ, and we are investigating the claims contained in the amended complaint and cooperating fully with the DOJ. Because these proceedings and investigations are in preliminary stages, we are unable to predict with any certainty the terms, or potential impact on our business or financial condition, of any potential resolution of these matters. Ordinary Course Matters We are also subject to other claims and lawsuits arising in the ordinary course of business, including potential claims related to, among other things, the care and treatment provided at our hospitals and outpatient facilities, the application of various federal and state labor laws, tax audits and other matters. Although the results of these claims and lawsuits cannot be predicted with certainty, we believe that the ultimate resolution of these ordinary course claims and lawsuits will not have a material effect on our business or financial condition. New claims or inquiries may be initiated against us from time to time. These matters could (1) require us to pay substantial damages or amounts in judgments or settlements, which, individually or in the aggregate, could exceed amounts, if any, that may be recovered under our insurance policies where coverage applies and is available, (2) cause us to incur substantial expenses, (3) require significant time and attention from our management, and (4) cause us to close or sell hospitals or otherwise modify the way we conduct business. The following table presents reconciliations of the beginning and ending liability balances in connection with legal settlements and related costs recorded in continuing operations during the years ended December 31, 2018 , 2017 and 2016 . No amounts were recorded in discontinued operations in the 2018, 2017 and 2016 periods. Balances at Beginning of Period Litigation and Investigation Costs Cash Payments Other Balances at End of Period Year Ended December 31, 2018 $ 12 $ 38 $ (41 ) $ (1 ) $ 8 Year Ended December 31, 2017 $ 12 $ 23 $ (23 ) $ — $ 12 Year Ended December 31, 2016 $ 299 $ 293 $ (582 ) $ 2 $ 12 For the years ended December 31, 2018 , 2017 and 2016 , we recorded net costs of $38 million , $23 million and $293 million , respectively, in connection with significant legal proceedings and governmental investigations. Of these amounts, $278 million

REDEEMABLE NONCONTROLLING INTER

REDEEMABLE NONCONTROLLING INTERESTS IN EQUITY OF CONSOLIDATED SUBSIDIARIES	12 Months Ended
	Dec. 31, 2018
Noncontrolling Interest [Abstract]
REDEEMABLE NONCONTROLLING INTERESTS IN EQUITY OF CONSOLIDATED SUBSIDIARIES	REDEEMABLE NONCONTROLLING INTERESTS IN EQUITY OF CONSOLIDATED SUBSIDIARIES As part of the acquisition of United Surgical Partners International, Inc., we entered into a put/call agreement (the “Put/Call Agreement”) with respect to the equity interests in USPI held by our joint venture partners. In April 2016, we paid $127 million to purchase shares put to us according to the Put/Call Agreement, which increased our ownership interest in USPI to approximately 56.3% . On May 1, 2017, we amended and restated the Put/Call Agreement to provide for, among other things, the acceleration of our acquisition of certain shares of USPI. Under the terms of the amendment, we paid Welsh Carson, on July 3, 2017, $716 million for the purchase of these shares, which increased our ownership interest in USPI to 80.0% , as well as the final adjustment to the 2016 purchase price. In April 2018, we paid $630 million for the purchase of an additional 15% ownership interest in USPI and the final adjustment to the 2017 purchase price, which increased our ownership interest in USPI to 95% . In addition, we entered into a separate put call agreement (the “Baylor Put/Call Agreement”) with Baylor University Medical Center (“Baylor”) that contains put and call options with respect to the 5% ownership interest in USPI held by Baylor. Each year starting in 2021, Baylor may put up to one-third of their total shares in USPI held as of January 1, 2017. In each year that Baylor does not put the full 33.3% of USPI’s shares allowable, we may call the difference between the number of shares Baylor put and the maximum number of shares they could have put that year. In addition, the Baylor Put/Call Agreement contains a call option pursuant to which we have the ability to acquire all of Baylor’s ownership interest by 2024. We have the ability to choose whether to settle the purchase price for the Baylor put/call in cash or shares of our common stock. Based on the nature of these put/call structures, the minority shareholders’ interests in USPI are classified as redeemable noncontrolling interests in the accompanying Consolidated Balance Sheets at December 31, 2018 and 2017 . The following table shows the changes in redeemable noncontrolling interests in equity of consolidated subsidiaries during the years ended 2018 and 2017 : December 31, 2018 2017 Balances at beginning of period $ 1,866 $ 2,393 Net income 190 239 Distributions paid to noncontrolling interests (142 ) (128 ) Accretion of redeemable noncontrolling interests 173 33 Purchases and sales of businesses and noncontrolling interests, net (667 ) (671 ) Balances at end of period $ 1,420 $ 1,866 Our redeemable noncontrolling interests balances at December 31, 2018 and 2017 in the table above were comprised of $431 million and $519 million , respectively, from our Hospital Operations and other segment, $713 million and $1.137 billion , respectively, from our Ambulatory Care segment, and $276 million and $210 million , respectively, from our Conifer segment. Our net income (loss) attributable to redeemable noncontrolling interests for the years ended December 31, 2018 and 2017 respectively, in the accompanying Consolidated Statements of Operations were comprised of $(25) million and $18 million , respectively, from our Hospital Operations and other segment, $151 million and $170 million , respectively, from our Ambulatory Care segment, and $64 million and $51 million

INCOME TAXES

INCOME TAXES	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXES The provision for income taxes for continuing operations for the years ended December 31, 2018 , 2017 and 2016 consists of the following: Years Ended December 31, 2018 2017 2016 Current tax expense (benefit): Federal $ (6 ) $ (4 ) $ 12 State 33 23 14 27 19 26 Deferred tax expense (benefit): Federal 159 202 34 State (10 ) (2 ) 7 149 200 41 $ 176 $ 219 $ 67 A reconciliation between the amount of reported income tax expense and the amount computed by multiplying income (loss) from continuing operations before income taxes by the statutory federal income tax rate is shown below. State income tax expense for the year ended December 31, 2018 includes $9 million of expense related to the write off of expired or worthless unutilized state net operating loss carryforwards and other deferred tax assets for which a full valuation allowance had been provided in prior years. A corresponding tax benefit of $9 million is included for the year ended December 31, 2018 to reflect the reduction in the valuation allowance. Foreign pre-tax loss for the years ended December 31, 2018 and 2017 was $6 million and $70 million , respectively. Years Ended December 31, 2018 2017 2016 Tax expense (benefit) at statutory federal rate of 21% in 2018 $ 134 $ (35 ) $ 87 State income taxes, net of federal income tax benefit 23 4 16 Expired state net operating losses, net of federal income tax benefit 9 28 35 Tax attributable to noncontrolling interests (70 ) (113 ) (106 ) Nondeductible goodwill 8 109 29 Nontaxable gains — — (11 ) Nondeductible litigation costs — — 37 Impact of decrease in federal tax rate on deferred taxes (1 ) 246 — Reversal of permanent reinvestment assumption and other adjustments (6 ) (30 ) — Stock-based compensation tax deficiencies 5 15 — Changes in valuation allowance (including impact of decrease in federal tax rate) 76 — (25 ) Change in tax contingency reserves, including interest (1 ) (6 ) (9 ) Prior-year provision to return adjustments and other changes in deferred taxes (5 ) 4 12 Other items 4 (3 ) 2 Income tax expense $ 176 $ 219 $ 67 In December 2017, the President signed into law the Tax Cuts and Jobs Act (the “Tax Act”). The Tax Act amended the Internal Revenue Code to reduce tax rates and modify policies, credits and deductions for individuals and businesses. For businesses, the Tax Act made broad and complex changes to the U.S. tax code, including but not limited to (1) reducing the corporate federal tax rate from a maximum of 35% to a flat 21% rate effective January 1, 2018, (2) repealing the corporate alternative minimum tax (“AMT”) and changing how existing AMT credits may be realized, (3) creating a new limitation on the deductibility of interest expense, (4) allowing full expensing of certain capital expenditures, and (5) denying deductions for performance-based compensation paid to certain key executives. International provisions in the Tax Act have not had, and are not expected to have, a material impact on the Company’s taxes. The staff of the U.S. Securities and Exchange Commission issued Staff Accounting Bulletin No. 118 (“SAB 118”), which provided guidance on accounting for the tax effects of the Tax Act. Pursuant to SAB 118, companies were permitted up to one year from the enactment of the Tax Act to complete the accounting under ASC 740 (“the measurement period”). We completed the accounting for the tax effects of the Tax Act within the measurement period. As a result of the reduction in the corporate income tax rate from 35% to 21% under the Tax Act, we revalued our net deferred tax assets at December 31, 2017, resulting in a reduction in the value of our net deferred tax assets by approximately $251 million . For the year ended December 31, 2017, we recorded $252 million as a provisional estimate of the impact of the Tax Act, including the decrease in the corporate income tax rate from 35% to 21%. Approximately $6 million of the total $252 million increase in income tax expense is included in the net change in valuation allowance, with the remaining $246 million shown in the table above. During the year ended December 31, 2018 , we recorded $1 million of tax benefit upon finalizing our accounting for the income tax effects of the Tax Act based on actual 2017 federal and state income tax filings. Deferred income taxes reflect the tax effects of temporary differences between the carrying amount of assets and liabilities for financial reporting purposes and the amount used for income tax purposes. The following table discloses those significant components of our deferred tax assets and liabilities, including any valuation allowance: December 31, 2018 December 31, 2017 Assets Liabilities Assets Liabilities Depreciation and fixed-asset differences $ — $ 297 $ — $ 411 Reserves related to discontinued operations and restructuring charges 24 — 15 — Receivables (doubtful accounts and adjustments) 155 — 134 — Deferred gain on debt exchanges — — — 6 Accruals for retained insurance risks 205 — 225 — Intangible assets — 341 — 330 Other long-term liabilities 39 — 97 — Benefit plans 255 — 268 — Other accrued liabilities 32 — 42 — Investments and other assets — 83 — 79 Interest expense limitation 89 — — — Net operating loss carryforwards 266 — 399 — Stock-based compensation 24 — 27 — Other items 88 32 142 32 1,177 753 1,349 858 Valuation allowance (148 ) — (72 ) — $ 1,029 $ 753 $ 1,277 $ 858 Below is a reconciliation of the deferred tax assets and liabilities and the corresponding amounts reported in the accompanying Consolidated Balance Sheets. December 31, 2018 2017 Deferred income tax assets $ 312 $ 455 Deferred tax liabilities (36 ) (36 ) Net deferred tax asset $ 276 $ 419 During the year ended December 31, 2018 , the valuation allowance increased by $76 million , including an increase of $89 million due to limitations on deductions of interest expense , a decrease of $9 million due to the expiration or worthlessness of unutilized state net operating loss carryovers, and a decrease of $4 million due to changes in expected realizability of deferred tax assets. The balance in the valuation allowance as of December 31, 2018 was $148 million . During the year ended December 31, 2017 , we had no net change in the valuation allowance, but there was a decrease of $28 million due to the expiration or worthlessness of unutilized state net operating loss carryovers, an increase of $6 million due to the decrease in the federal tax rate, and an increase of $22 million due to changes in expected realizability of deferred tax assets. The remaining balance in the valuation allowance at December 31, 2017 was $72 million . During the year ended December 31, 2016, the valuation allowance decreased by $24 million primarily due to the expiration or worthlessness of unutilized state net operating loss carryovers. The balance in the valuation allowance as of December 31, 2016 was $72 million . We account for uncertain tax positions in accordance with ASC 740-10-25, which prescribes a comprehensive model for the financial statement recognition, measurement, presentation and disclosure of uncertain tax positions taken or expected to be taken in income tax returns. The following table summarizes the total changes in unrecognized tax benefits in continuing operations during the years ended December 31, 2018 , 2017 and 2016 . There were no such changes in discontinued operations. The additions and reductions for tax positions include the impact of items for which the ultimate deductibility is highly certain, but for which there is uncertainty about the timing of such deductions. Such amounts include unrecognized tax benefits that have impacted deferred tax assets and liabilities at December 31, 2018 , 2017 and 2016 . Continuing Operations Balance At December 31, 2015 $ 40 Additions for prior-year tax positions 2 Reductions due to a lapse of statute of limitations (7 ) Balance At December 31, 2016 $ 35 Additions for prior-year tax positions 31 Reductions for tax positions of prior years (15 ) Reductions due to a lapse of statute of limitations (5 ) Balance At December 31, 2017 $ 46 Reductions due to a lapse of statute of limitations (1 ) Balance At December 31, 2018 $ 45 The total amount of unrecognized tax benefits as of December 31, 2018 was $45 million , of which $43 million , if recognized, would affect our effective tax rate and income tax expense (benefit) from continuing operations. Income tax expense in the year ended December 31, 2018 includes a benefit of $1 million in continuing operations attributable to a decrease in our estimated liabilities for uncertain tax positions, net of related deferred tax effects. The total amount of unrecognized tax benefits as of December 31, 2017 was $46 million , of which $44 million , if recognized, would affect our effective tax rate and income tax expense (benefit) from continuing operations. Income tax expense in the year ended December 31, 2017 includes a benefit of $5 million in continuing operations attributable to a decrease in our estimated liabilities for uncertain tax positions, net of related deferred tax effects. The total amount of unrecognized tax benefits as of December 31, 2016 was $35 million , of which $32 million , if recognized, would affect our effective tax rate and income tax expense (benefit) from continuing operations. Income tax expense in the year ended December 31, 2016 includes a benefit of $9 million in continuing operations attributable to a decrease in our estimated liabilities for uncertain tax positions, net of related deferred tax effects. Our practice is to recognize interest and penalties related to income tax matters in income tax expense in our consolidated statements of operations. Approximately $1 million of interest and penalties related to accrued liabilities for uncertain tax positions related to continuing operations are included in the accompanying Consolidated Statement of Operations for the year ended December 31, 2018 . Total accrued interest and penalties on unrecognized tax benefits as of December 31, 2018 were $3 million , all of which related to continuing operations. The Internal Revenue Service (“IRS”) has completed audits of our tax returns for all tax years ended on or before December 31, 2007. All disputed issues with respect to these audits have been resolved and all related tax assessments (including interest) have been paid. Our tax returns for years ended after December 31, 2007 and USPI’s tax returns for years ended after December 31, 2014 remain subject to audit by the IRS. As of December 31, 2018 , approximately $10 million of unrecognized federal and state tax benefits, as well as reserves for interest and penalties, may decrease in the next 12 months as a result of the settlement of audits, the filing of amended tax returns or the expiration of statutes of limitations. At December 31, 2018 , our carryforwards available to offset future taxable income consisted of (1) federal net operating loss (“NOL”) carryforwards of approximately $1.0 billion pre-tax expiring in 2027 to 2034 , (2) general business credit carryforwards of approximately $26 million expiring in 2023 through 2038, and (3) state NOL carryforwards of approximately $3.1 billion expiring in 2019 through 2038 for which the associated deferred tax benefit, net of valuation allowance and federal tax impact, is $22 million . Our ability to utilize NOL carryforwards to reduce future taxable income may be limited under Section 382 of the Internal Revenue Code if certain ownership changes in our company occur during a rolling three -year period. These ownership changes include purchases of common stock under share repurchase programs , the offering of stock by us, the purchase or sale of our stock by 5% shareholders, as defined in the Treasury regulations, or the issuance or exercise of rights to acquire our stock. If such ownership changes by 5% shareholders result in aggregate increases that exceed 50 percentage points during the three -year period, then Section 382 imposes an annual limitation on the amount of our taxable income that may be offset by the NOL carryforwards or tax credit carryforwards at the time of ownership change.

EARNINGS (LOSS) PER COMMON SHAR

EARNINGS (LOSS) PER COMMON SHARE	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
EARNINGS (LOSS) PER COMMON SHARE	EARNINGS (LOSS) PER COMMON SHARE The following table is a reconciliation of the numerators and denominators of our basic and diluted earnings (loss) per common share calculations for our continuing operations for the years ended December 31, 2018 , 2017 and 2016 . Net earnings available (loss attributable) is expressed in millions and weighted average shares are expressed in thousands. Net Income Available (Loss Attributable) to Common Shareholders (Numerator) Weighted Average Shares (Denominator) Per-Share Amount Year Ended December 31, 2018 Net income available to Tenet Healthcare Corporation common shareholders for basic earnings per share $ 108 102,110 $ 1.06 Effect of dilutive stock options, restricted stock units and deferred compensation units — 1,771 (0.02 ) Net income available to Tenet Healthcare Corporation common shareholders for diluted earnings per share $ 108 103,881 $ 1.04 Year Ended December 31, 2017 Net loss attributable to Tenet Healthcare Corporation common shareholders for basic loss per share $ (704 ) 100,592 $ (7.00 ) Effect of dilutive stock options, restricted stock units and deferred compensation units — — — Net loss attributable to Tenet Healthcare Corporation common shareholders for diluted loss per share $ (704 ) 100,592 $ (7.00 ) Year Ended December 31, 2016 Net loss attributable to Tenet Healthcare Corporation common shareholders for basic losss per share $ (187 ) 99,321 $ (1.88 ) Effect of dilutive stock options, restricted stock units and deferred compensation units — — — Net loss attributable to Tenet Healthcare Corporation common shareholders for diluted earnings per share $ (187 ) 99,321 $ (1.88 ) All potentially dilutive securities were excluded from the calculation of diluted loss per share for the years ended December 31, 2017 and 2016 because we did not report income from continuing operations available to common shareholders in those periods. In circumstances where we do not have income from continuing operations available to common shareholders, the effect of stock options and other potentially dilutive securities is anti-dilutive, that is, a loss from continuing operations attributable to common shareholders has the effect of making the diluted loss per share less than the basic loss per share. Had we generated income from continuing operations available to common shareholders in the years ended December 31, 2017 and 2016 , the effect (in thousands) of employee stock options, restricted stock units and deferred compensation units on the diluted shares calculation would have been an increase in shares of 788 and 1,421 for the years ended December 31, 2017 and 2016

FAIR VALUE MEASUREMENTS

FAIR VALUE MEASUREMENTS	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
FAIR VALUE MEASUREMENTS	FAIR VALUE MEASUREMENTS Our non-financial assets and liabilities not permitted or required to be measured at fair value on a recurring basis typically relate to long-lived assets held and used, long-lived assets held for sale and goodwill. We are required to provide additional disclosures about fair value measurements as part of our financial statements for each major category of assets and liabilities measured at fair value on a non-recurring basis. The following tables present this information and indicate the fair value hierarchy of the valuation techniques we utilized to determine such fair values. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities, which generally are not applicable to non-financial assets and liabilities. Fair values determined by Level 2 inputs utilize data points that are observable, such as definitive sales agreements, appraisals or established market values of comparable assets. Fair values determined by Level 3 inputs are unobservable data points for the asset or liability and include situations where there is little, if any, market activity for the asset or liability, such as internal estimates of future cash flows. . December 31, 2018 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Long-lived assets held for sale $ 39 $ — $ 39 $ — Long-lived assets held and used $ 130 $ — $ 130 $ — December 31, 2017 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Long-lived assets held for sale $ 456 $ — $ 456 $ — Long-lived assets held and used $ — $ — $ — $ — Other than temporarily impaired equity method investments $ 113 $ — $ 113 $ — As described in Note 6 , in the year ended December 31, 2018 , we recorded impairment charges in continuing operations of $40 million for the write-down of buildings and other long-lived assets to their estimated fair values at two hospitals. We also recorded $24 million to write-down assets held for sale to their estimated fair value, less estimated costs to sell, for certain of our Chicago-area facilities, as well as $9 million of impairment charges to write-down assets held for sale to their estimated fair value, less estimated costs to sell, for Aspen and $4 million related to other impairment charges. In the year ended December 31, 2017 , we recorded $364 million for the write-down of assets held for sale to their estimated fair value, less estimated costs to sell, for Aspen, our Philadelphia-area facilities and certain of our Chicago-area facilities, as well as $31 million of impairment charges related to investments and $7 million related to other intangible assets, primarily contract-related intangibles and capitalized software costs not associated with the hospitals described above. The fair value of our long-term debt (except for borrowings under the Credit Agreement) is based on quoted market prices (Level 1). The inputs used to establish the fair value of the borrowings outstanding under the Credit Agreement are considered to be Level 2 inputs, which include inputs other than quoted prices included in Level 1 that are observable, either directly or indirectly. At December 31, 2018 and 2017 , the estimated fair value of our long-term debt was approximately 97.3% and 100.2%

ACQUISITIONS

ACQUISITIONS	12 Months Ended
	Dec. 31, 2018
Business Combinations [Abstract]
ACQUISITIONS	ACQUISITIONS During the year ended December 31, 2018 , we acquired ten outpatient businesses (all of which are owned by USPI), three off-campus emergency departments and various physician practices. The fair value of the consideration conveyed in the acquisitions (the “purchase price”) was $113 million . During the year ended December 31, 2017 , we acquired eight outpatient businesses (all of which are owned by USPI) and various physician practices. The fair value of the consideration conveyed in the acquisitions (the “purchase price”) was $50 million . During the year ended December 31, 2016 , we completed a transaction that allowed us to consolidate five microhospitals that were previously recorded as equity method investments. We also acquired majority interests in 28 ambulatory surgery centers (all of which are owned USPI) and various physician practices. The fair value of the consideration conveyed in the acquisitions (the “purchase price”) was $117 million . We are required to allocate the purchase prices of acquired businesses to assets acquired or liabilities assumed and, if applicable, noncontrolling interests based on their fair values. The excess of the purchase price allocated over those fair values is recorded as goodwill. The purchase price allocations for certain acquisitions completed in 2018 is preliminary. We are in process of finalizing the purchase price allocations, including valuations of the acquired property and equipment, other intangible assets and noncontrolling interests for some of our 2018 acquisitions; therefore, those purchase price allocations are subject to adjustment once the valuations are completed. Preliminary or final purchase price allocations for all the acquisitions made during the years ended December 31, 2018 , 2017 and 2016 are as follows: 2018 2017 2016 Current assets $ 6 $ 7 $ 51 Property and equipment 19 9 38 Other intangible assets 9 8 7 Goodwill 220 91 464 Other long-term assets, including previously held equity method investments (18 ) (3 ) (56 ) Current liabilities — (8 ) (30 ) Long-term liabilities (15 ) (2 ) (15 ) Redeemable noncontrolling interests in equity of consolidated subsidiaries (21 ) (29 ) (190 ) Noncontrolling interests (85 ) (18 ) (119 ) Cash paid, net of cash acquired (113 ) (50 ) (117 ) Gains on consolidations $ 2 $ 5 $ 33 The goodwill generated from these transactions, the majority of which will not be deductible for income tax purposes, can be attributed to the benefits that we expect to realize from operating efficiencies and growth strategies. Of the total $220 million of goodwill recorded for acquisitions completed during the year ended December 31, 2018 , $1 million was recorded in our Hospital Operations and other segment, and $219 million was recorded in our Ambulatory Care segment. Approximately $10 million , $6 million and $20 million in transaction costs related to prospective and closed acquisitions were expensed during the years ended December 31, 2018 , 2017 and 2016 , respectively, and are included in impairment and restructuring charges, and acquisition-related costs in the accompanying Consolidated Statements of Operations. During the years ended December 31, 2018 , 2017 and 2016 , we recognized gains totaling $2 million , $5 million and $33 million

SEGMENT INFORMATION

SEGMENT INFORMATION	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
SEGMENT INFORMATION	SEGMENT INFORMATION Our business consists of our Hospital Operations and other segment, our Ambulatory Care segment and our Conifer segment. The factors for determining the reportable segments include the manner in which management evaluates operating performance combined with the nature of the individual business activities. Our Hospital Operations and other segment is comprised of our acute care and specialty hospitals, ancillary outpatient facilities, urgent care centers, microhospitals and physician practices. As described in Note 5 , certain of our facilities were classified as held for sale in the accompanying Consolidated Balance Sheet at December 31, 2018 . At December 31, 2018 , our subsidiaries operated 68 hospitals ( three of which have since been divested), primarily serving urban and suburban communities in 10 states. Our Ambulatory Care segment is comprised of the operations of USPI and included nine Aspen facilities in the United Kingdom until their divestiture effective August 17, 2018. At December 31, 2018 , USPI had interests in 255 ambulatory surgery centers, 36 urgent care centers operated under the CareSpot brand, 23 imaging centers and 23 surgical hospitals in 27 states. At December 31, 2018 , we owned 95.0% of USPI. Our Conifer segment provides healthcare business process services in the areas of hospital and physician revenue cycle management and value-based care solutions to healthcare systems, as well as individual hospitals, physician practices, self-insured organizations, health plans and other entities . At December 31, 2018 , Conifer provided services to approximately 750 Tenet and non-Tenet hospitals and other clients nationwide. In 2012, we entered into agreements documenting the terms and conditions of various services Conifer provides to Tenet hospitals, as well as certain administrative services our Hospital Operations and other segment provides to Conifer. The pricing terms for the services provided by each party to the other under these contracts were based on estimated third-party pricing terms in effect at the time the agreements were signed. At December 31, 2018 , we owned 76.2% of Conifer Health Solutions, LLC, which is the principal subsidiary of Conifer Holdings, Inc. The following table includes amounts for each of our reportable segments and the reconciling items necessary to agree to amounts reported in the accompanying Consolidated Balance Sheets and Consolidated Statements of Operations: December 31, December 31, December 31, Assets: Hospital Operations and other $ 15,684 $ 16,466 $ 17,871 Ambulatory Care 5,711 5,822 5,722 Conifer 1,014 1,097 1,108 Total $ 22,409 $ 23,385 $ 24,701 Years Ended December 31, 2018 2017 2016 Capital expenditures: Hospital Operations and other $ 527 $ 625 $ 799 Ambulatory Care 68 60 51 Conifer 22 22 25 Total $ 617 $ 707 $ 875 Net operating revenues: Hospital Operations and other total prior to inter-segment eliminations $ 15,285 $ 16,260 $ 16,904 Ambulatory Care 2,085 1,940 1,797 Conifer Tenet 590 618 651 Other clients 943 979 920 Total Conifer revenues 1,533 1,597 1,571 Inter-segment eliminations (590 ) (618 ) (651 ) Total $ 18,313 $ 19,179 $ 19,621 Equity in earnings of unconsolidated affiliates: Hospital Operations and other $ 10 $ 4 $ 9 Ambulatory Care 140 140 122 Total $ 150 $ 144 $ 131 Adjusted EBITDA: Hospital Operations and other $ 1,411 $ 1,462 $ 1,586 Ambulatory Care 792 699 615 Conifer 357 283 277 Total $ 2,560 $ 2,444 $ 2,478 Depreciation and amortization: Hospital Operations and other $ 685 $ 736 $ 709 Ambulatory Care 68 84 91 Conifer 49 50 50 Total $ 802 $ 870 $ 850 Adjusted EBITDA $ 2,560 $ 2,444 $ 2,478 Income (loss) from divested and closed businesses 9 (41 ) (37 ) Depreciation and amortization (802 ) (870 ) (850 ) Impairment and restructuring charges, and acquisition-related costs (209 ) (541 ) (202 ) Litigation and investigation costs (38 ) (23 ) (293 ) Interest expense (1,004 ) (1,028 ) (979 ) Gain (loss) from early extinguishment of debt 1 (164 ) — Other non-operating expense, net (5 ) (22 ) (20 ) Net gains on sales, consolidation and deconsolidation of facilities 127 144 151 Income (loss) from continuing operations, before income taxes $ 639 $ (101 ) $ 248

RECENT ACCOUNTING STANDARDS

RECENT ACCOUNTING STANDARDS	12 Months Ended
	Dec. 31, 2018
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
RECENT ACCOUNTING STANDARDS	RECENT ACCOUNTING STANDARDS Recently Issued Accounting Standards In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)” (“ASU 2016-02”), which affects any entity that enters into a lease (as that term is defined in ASU 2016-02), with some specified scope exceptions. The main difference between the guidance in ASU 2016-02 and current GAAP is the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under current GAAP. Under ASU 2016-02, lessees and lessors are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach, which includes a number of optional practical expedients. In July 2018, the FASB issued ASU 2018-11 “Leases (Topic 842) Targeted Improvements,” which allows lessees and lessors to recognize and measure leases at the beginning of the period of adoption without modifying the comparative period financial statements. This guidance will be effective for us beginning in 2019, and we intend to use the retrospective method as of the period of adoption rather than the earliest period presented meaning that our financial statements for periods prior to January 1, 2019 will not be modified for the application of the new lease accounting standard. We will elect the three packaged transition practical expedients under ASC 842-10-65-1(f) and the practical expedient that allows lessees to choose to not separate lease and non-lease components by class of underlying asset. We expect that, as of January 1, 2019, our consolidated assets and liabilities will both increase by approximately $750 million to $800 million related to on-balance sheet recognition of right of use assets and liabilities. Right of use assets associated with operating leases will be included as an intangible asset, and liabilities associated with operating leases will be split between our other current liabilities and other long-term liabilities in our consolidated balance sheets. We are still finalizing our calculation of the cumulative effect of accounting change we will recognize upon adoption. We are currently working to complete the implementation of new processes and information technology tools to assist in our ongoing lease data collection and analysis, and updating our accounting policies and internal controls in connection with the adoption of the new standard. In August 2018, the FASB issued ASU 2018-13, “Fair Value Measurement (Topic 820) Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement” (“ASU 2018-13”), which applies to all entities that are required to make disclosures about recurring or nonrecurring fair value measurements. The amendments in ASU 2018-13, which remove, modify or add certain disclosure requirements as part of the FASB’s disclosure framework project to improve the effectiveness of the notes to the financial statements, are effective for us beginning in 2020. The adoption of this guidance will not impact our financial position, results of operations or cash flows. Also in August 2018, the FASB issued ASU 2018-14, “Compensation – Retirement Benefits – Defined Benefit Plans –General (Subtopic 715-20) Disclosure Framework—Changes to the Disclosure Requirements for Defined Benefit Plans” (“ASU 2018-14”), which applies to all employers that sponsor defined benefit pension or other postretirement plans. The amendments in ASU 2018-14, which remove, modify or add certain disclosure requirements as part of the FASB’s disclosure framework project to improve the effectiveness of the notes to the financial statements, are effective for us beginning in 2021. The adoption of this guidance will not impact our financial position, results of operations or cash flows. Additionally, the FASB issued ASU 2018-15, “Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-40) Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract” (“ASU 2018-14”), which applies to all entities that are a customer in a hosting arrangement that is a service contract. The amendments in ASU 2018-14, which align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software, are effective for us beginning in 2020. We do not expect adoption of this guidance to have a material effect on our financial position, results of operations or cash flows. Recently Adopted Accounting Standards Effective January 1, 2018, as further discussed in Note 1, we adopted ASU 2014-09 and ASU 2016-01, and we early adopted ASU 2018-02. Also effective January 1, 2018, we adopted ASU 2016-15, “Statement of Cash Flows (Topic 230) Classification of Certain Cash Receipts and Cash Payments” and ASU 2016-18, “Statement of Cash Flows (Topic 230) Restricted Cash,” both of which were applied using a retrospective transition method to each period presented and did not have any effect on our statements of cash flows. Effective January 1, 2017, as further discussed in Note 1, we adopted ASU 2016-09 and early adopted ASU 2017-07. We also early adopted ASU 2017-04, “Intangibles – Goodwill and Other (Topic 350)” (“ASU 2017‑04”) for our annual goodwill impairment tests for the year ended December 31, 2017. The amendments in ASU 2017-04 modified the concept of impairment from the condition that exists when the carrying amount of goodwill exceeds its implied fair value to the condition that exists when the carrying amount of a reporting unit exceeds its fair value. An entity no longer determines goodwill

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	12 Months Ended
	Dec. 31, 2018
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENT On February 5, 2019, we sold $1.5 billion aggregate principal amount of 6.250% senior secured second lien notes, which will mature on February 1, 2027 (the “2027 Senior Secured Second Lien Notes”). We will pay interest on the 2027 Senior Secured Second Lien Notes semi-annually in arrears on February 1 and August 1 of each year, which payments will commence on August 1, 2019. The proceeds from the sale of the 2027 Senior Secured Second Lien Notes were used, after payment of fees and expenses, together with cash on hand and borrowings under our Credit Agreement, to fund the redemption of all $300 million aggregate principal amount of our outstanding 6.750% senior notes due 2020 and all $750 million aggregate principal amount of our outstanding 7.500% senior secured second lien notes due 2022, and will be used to fund the repayment upon maturity of all $468 million aggregate principal amount of our outstanding 5.500% senior unsecured notes due March 1, 2019. In connection with the redemptions, we expect to record a loss from early extinguishment of debt of approximately $47 million in the three months ending March 31, 2019 , primarily related to the difference between the redemption prices and the par values of the notes, as well as the write-off of the associated unamortized issuance costs. As a result of these refinancing transactions, our 5.500% senior unsecured notes due 2019 are not included in current portion of long-term debt in our Consolidated Balance Sheet at December 31, 2018

Supplemental Financial Informat

Supplemental Financial Information	12 Months Ended
	Dec. 31, 2018
Condensed Financial Information Disclosure [Abstract]
Supplemental Financial Information	SUPPLEMENTAL FINANCIAL INFORMATION SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) Year Ended December 31, 2018 First Second Third Fourth Net operating revenues $ 4,699 $ 4,506 $ 4,489 $ 4,619 Net income $ 191 $ 108 $ 65 $ 102 Net income available (loss attributable) to Tenet Healthcare Corporation common shareholders $ 99 $ 26 $ (9 ) $ (5 ) Earnings (loss) per share available (attributable) to Tenet Healthcare Corporation common shareholders: Basic $ 0.98 $ 0.25 $ (0.09 ) $ (0.04 ) Diluted $ 0.96 $ 0.25 $ (0.09 ) $ (0.04 ) Year Ended December 31, 2017 First Second Third Fourth Net operating revenues $ 4,813 $ 4,802 $ 4,586 $ 4,978 Net income (loss) $ 36 $ 32 $ (289 ) $ (99 ) Net loss attributable to Tenet Healthcare Corporation common shareholders $ (53 ) $ (55 ) $ (367 ) $ (229 ) Loss per share attributable to Tenet Healthcare Corporation common shareholders: Basic $ (0.53 ) $ (0.55 ) $ (3.64 ) $ (2.27 ) Diluted $ (0.53 ) $ (0.55 ) $ (3.64 ) $ (2.27 )

SCHEDULE II-VALUATION AND QUALI

SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS	12 Months Ended
	Dec. 31, 2018
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS	SCHEDULE II—VALUATION AND QUALIFYING ACCOUNTS (In Millions) Additions Charged To: Balance at Beginning of Period Costs and Expenses (1)(2) Deductions (3) Other Items (4)(5) Balance at End of Period Allowance for doubtful accounts: Year ended December 31, 2018 $ 898 $ — $ — $ (898 ) $ — Year ended December 31, 2017 $ 1,031 $ 1,434 $ (1,445 ) $ (122 ) $ 898 Year ended December 31, 2016 $ 887 $ 1,451 $ (1,307 ) $ — $ 1,031 Valuation allowance for deferred tax assets: Year ended December 31, 2018 $ 72 $ 76 $ — $ — $ 148 Year ended December 31, 2017 $ 72 $ — $ — $ — $ 72 Year ended December 31, 2016 $ 96 $ (24 ) $ — $ — $ 72 (1) Includes amounts recorded in discontinued operations. (2) Before considering recoveries on accounts or notes previously written off. (3) Accounts written off. (4) Acquisition and divestiture activity in 2017. (5)

SIGNIFICANT ACCOUNTING POLICI_2

SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation Our Consolidated Financial Statements include the accounts of Tenet and its wholly owned and majority-owned subsidiaries. We eliminate intercompany accounts and transactions in consolidation, and we include the results of operations of businesses that are newly acquired in purchase transactions from their dates of acquisition. We account for significant investments in other affiliated companies using the equity method. Unless otherwise indicated, all financial and statistical data included in these notes to our Consolidated Financial Statements relate to our continuing operations, with dollar amounts expressed in millions (except per-share amounts). Effective January 1, 2018, we adopted the Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) 2014-09, “Revenue from Contracts with Customers (Topic 606)” (“ASU 2014-09”) using a modified retrospective method of application to all contracts existing on January 1, 2018. The core principle of the guidance in ASU 2014-09 is that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. For our Hospital Operations and other and Ambulatory Care segments, the adoption of ASU 2014-09 resulted in changes to our presentation and disclosure of revenue primarily related to uninsured or underinsured patients. Prior to the adoption of ASU 2014-09, a significant portion of our provision for doubtful accounts related to self-pay patients, as well as co-pays, co-insurance amounts and deductibles owed to us by patients with insurance. Under ASU 2014-09, the estimated uncollectable amounts due from these patients are generally considered implicit price concessions that are a direct reduction to net operating revenues, with a corresponding material reduction in the amounts presented separately as provision for doubtful accounts. For the year ended December 31, 2018 , we recorded approximately $1.422 billion of implicit price concessions as a direct reduction of net operating revenues that would have been recorded as provision for doubtful accounts prior to the adoption of ASU 2014-09. At January 1, 2018, we reclassified $171 million of revenues related to patients who were still receiving inpatient care in our facilities at that date from accounts receivable, less allowance for doubtful accounts, to contract assets, which are included in other current assets in the accompanying Consolidated Balance Sheet at December 31, 2018 . The adoption of ASU 2014-09 also resulted in changes to our presentation and disclosure of customer contract assets and liabilities and the assessment of variable consideration under customer contracts, which are further discussed in Note 4. Also effective January 1, 2018, we early adopted ASU 2018-02, “Income Statement – Reporting Comprehensive Income (Topic 220)” (“ASU 2018-02”), which allows a reclassification from accumulated other comprehensive income to retained earnings for stranded income tax effects resulting from the Tax Cuts and Jobs Act (the “Tax Act”) and requires certain disclosures about stranded income tax effects. We applied the amendments in ASU 2018-02 in the period of adoption, resulting in a reclassification that decreased accumulated deficit and increased accumulated other comprehensive loss by $36 million of stranded income tax effects in the year ended December 31, 2018. In addition, we adopted ASU 2016-01, “Financial Instruments – Overall (Subtopic 825-10) Recognition and Measurement of Financial Assets and Financial Liabilities” (“ASU 2016-01”) effective January 1, 2018, which supersedes the guidance to classify equity securities with readily determinable fair values into different categories (that is, trading or available-for-sale) and require equity securities (including other ownership interests, such as partnerships, unincorporated joint ventures and limited liability companies) to be measured at fair value with changes in the fair value recognized through net income. Upon adoption of ASU 2016-01 on January 1, 2018, we recorded a cumulative effect adjustment to decrease accumulated deficit by $7 million for unrealized gains on equity securities. Effective January 1, 2017, we adopted ASU 2016-09, “Compensation – Stock Compensation (Topic 718) Improvements to Employee Share-Based Payment Accounting” (“ASU 2016-09”), which affects all entities that issue share-based payment awards to their employees. The guidance in ASU 2016-09 simplifies several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. Upon adoption of ASU 2016-09, we recorded previously unrecognized excess tax benefits of $56 million as a deferred tax asset and a cumulative effect adjustment to accumulated deficit as of January 1, 2017. Prospectively, all excess tax benefits and deficiencies will be recognized as income tax benefit or expense in our consolidated statement of operations when awards vest. Also effective January 1, 2017, we early adopted ASU 2017-07, “Compensation – Retirement Benefits (Topic 715) Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost” (“ASU 2017-07”), which the FASB issued in March 2017. The amendments in ASU 2017-07 apply to all employers that offer to their employees defined benefit pension plans, other postretirement benefit plans, or other types of benefits accounted for under Topic 715 of the FASB Accounting Standards Codification (“ASC”). The guidance in ASU 2017-07 requires that an employer report the service cost component in the same line item or items as other compensation costs arising from services rendered by the pertinent employees during the period. The other components of net periodic benefit cost are required to be presented in the statement of operations separately from the service cost component and outside a subtotal of income from operations. The line item or items used in the statement of operations to present the other components of net periodic benefit cost must be disclosed. The amendments in ASU 2017-07 must be applied retrospectively for the presentation of the service cost component and the other components of net periodic pension cost and net periodic postretirement benefit cost in the statement of operations. As a result of the adoption of ASU 2017-07, we reclassified $28 million of net periodic benefit cost from salaries, wages and benefits expense to other non-operating expense, net, in the accompanying Consolidated Statements of Operations for the year ended December 31, 2016, and $16 million and $31 million of other components of net periodic benefit cost are included in other non-operating expense, net, in the accompanying Consolidated Statement of Operations for the years ended December 31, 2018 and 2017
Use of Estimates	Use of Estimates
Translation of Foreign Currencies	Translation of Foreign Currencies
Net Operating Revenues	Net Operating Revenues ASU 2014-09 was issued to clarify the principles for recognizing revenue, to remove inconsistencies and weaknesses in revenue recognition requirements, and to provide a more robust framework for addressing revenue issues. Our adoption of ASU 2014-09 was accomplished using a modified retrospective method of application, and our accounting policies related to revenues were revised accordingly effective January 1, 2018, as discussed below. We recognize net operating revenues in the period in which we satisfy our performance obligations under contracts by transferring our services to our customers. Net operating revenues are recognized in the amounts to which we expect to be entitled, which are the transaction prices allocated to the distinct services. Net operating revenues for our Hospital Operations and other and Ambulatory Care segments primarily consist of net patient service revenues, principally for patients covered by Medicare, Medicaid, managed care and other health plans, as well as certain uninsured patients under our Compact with Uninsured Patients (“ Compact ”) and other uninsured discount and charity programs. Net operating revenues for our Conifer segment primarily consist of revenues from providing revenue cycle management services to healthcare systems, as well as individual hospitals, physician practices, self-insured organizations, health plans and other entities. Net Patient Service Revenues— We report net patient service revenues at the amounts that reflect the consideration to which we expect to be entitled in exchange for providing patient care. These amounts are due from patients, third-party payers (including managed care payers and government programs) and others, and they include variable consideration for retroactive revenue adjustments due to settlement of audits, reviews and investigations. Generally, we bill our patients and third-party payers several days after the services are performed or shortly after discharge. Revenues are recognized as performance obligations are satisfied. We determine performance obligations based on the nature of the services we provide. We recognize revenues for performance obligations satisfied over time based on actual charges incurred in relation to total expected charges. We believe that this method provides a faithful depiction of the transfer of services over the term of performance obligations based on the inputs needed to satisfy the obligations. Generally, performance obligations satisfied over time relate to patients in our hospitals receiving inpatient acute care services. We measure performance obligations from admission to the point when there are no further services required for the patient, which is generally the time of discharge. We recognize revenues for performance obligations satisfied at a point in time, which generally relate to patients receiving outpatient services, when: (1) services are provided; and (2) we do not believe the patient requires additional services. Because our patient service performance obligations relate to contracts with a duration of less than one year, we have elected to apply the optional exemption provided in ASC 606-10-50-14(a) and, therefore, we are not required to disclose the aggregate amount of the transaction price allocated to performance obligations that are unsatisfied or partially unsatisfied at the end of the reporting period. The unsatisfied or partially unsatisfied performance obligations referred to above are primarily related to inpatient acute care services at the end of the reporting period. The performance obligations for these contracts are generally completed when the patients are discharged, which generally occurs within days or weeks of the end of the reporting period. We determine the transaction price based on gross charges for services provided, reduced by contractual adjustments provided to third-party payers, discounts provided to uninsured patients in accordance with our Compact , and implicit price concessions provided primarily to uninsured patients. We determine our estimates of contractual adjustments and discounts based on contractual agreements, our discount policies and historical experience. We determine our estimate of implicit price concessions based on our historical collection experience with these classes of patients using a portfolio approach as a practical expedient to account for patient contracts as collective groups rather than individually. The financial statement effects of using this practical expedient are not materially different from an individual contract approach. Gross charges are retail charges. They are not the same as actual pricing, and they generally do not reflect what a hospital is ultimately paid and, therefore, are not displayed in our consolidated statements of operations. Hospitals are typically paid amounts that are negotiated with insurance companies or are set by the government. Gross charges are used to calculate Medicare outlier payments and to determine certain elements of payment under managed care contracts (such as stop-loss payments). Because Medicare requires that a hospital’s gross charges be the same for all patients (regardless of payer category), gross charges are what hospitals charge all patients prior to the application of discounts and allowances. Revenues under the traditional fee-for-service Medicare and Medicaid programs are based primarily on prospective payment systems. Retrospectively determined cost-based revenues under these programs, which were more prevalent in earlier periods, and certain other payments, such as Indirect Medical Education, Direct Graduate Medical Education, disproportionate share hospital and bad debt expense reimbursement, which are based on our hospitals’ cost reports, are estimated using historical trends and current factors. Cost report settlements under these programs are subject to audit by Medicare and Medicaid auditors and administrative and judicial review, and it can take several years until final settlement of such matters is determined and completely resolved. Because the laws, regulations, instructions and rule interpretations governing Medicare and Medicaid reimbursement are complex and change frequently, the estimates we record could change by material amounts. We have a system and estimation process for recording Medicare net patient service revenue and estimated cost report settlements. As a result, we record accruals to reflect the expected final settlements on our cost reports. For filed cost reports, we record the accrual based on those cost reports and subsequent activity, and record a valuation allowance against those cost reports based on historical settlement trends. The accrual for periods for which a cost report is yet to be filed is recorded based on estimates of what we expect to report on the filed cost reports, and a corresponding valuation allowance is recorded as previously described. Cost reports generally must be filed within five months after the end of the annual cost reporting period. After the cost report is filed, the accrual and corresponding valuation allowance may need to be adjusted. Settlements with third-party payers for retroactive revenue adjustments due to audits, reviews or investigations are considered variable consideration and are included in the determination of the estimated transaction price for providing patient care using the most likely outcome method. These settlements are estimated based on the terms of the payment agreement with the payer, correspondence from the payer and our historical settlement activity, including an assessment to ensure that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the retroactive adjustment is subsequently resolved. Estimated settlements are adjusted in future periods as adjustments become known (that is, new information becomes available), or as years are settled or are no longer subject to such audits, reviews and investigations. Revenues under managed care plans are based primarily on payment terms involving predetermined rates per diagnosis, per-diem rates, discounted fee-for-service rates and/or other similar contractual arrangements. These revenues are also subject to review and possible audit by the payers, which can take several years before they are completely resolved. The payers are billed for patient services on an individual patient basis. An individual patient’s bill is subject to adjustment on a patient-by-patient basis in the ordinary course of business by the payers following their review and adjudication of each particular bill. We estimate the discounts for contractual allowances at the individual hospital level utilizing billing data on an individual patient basis. At the end of each month, on an individual hospital basis, we estimate our expected reimbursement for patients of managed care plans based on the applicable contract terms. Contractual allowance estimates are periodically reviewed for accuracy by taking into consideration known contract terms, as well as payment history. We believe our estimation and review process enables us to identify instances on a timely basis where such estimates need to be revised. We do not believe there were any adjustments to estimates of patient bills that were material to our revenues. In addition, on a corporate-wide basis, we do not record any general provision for adjustments to estimated contractual allowances for managed care plans. Managed care accounts, net of contractual allowances recorded, are further reduced to their net realizable value through implicit price concessions based on historical collection trends for these payers and other factors that affect the estimation process. We know of no claims, disputes or unsettled matters with any payer that would materially affect our revenues for which we have not adequately provided in the accompanying Consolidated Financial Statements. Generally, patients who are covered by third-party payers are responsible for related co-pays, co-insurance and deductibles, which vary in amount. We also provide services to uninsured patients and offer uninsured patients a discount from standard charges. We estimate the transaction price for patients with co-pays, co-insurance and deductibles and for those who are uninsured based on historical collection experience and current market conditions. Under our Compact and other uninsured discount programs, the discount offered to certain uninsured patients is recognized as a contractual allowance, which reduces net operating revenues at the time the self-pay accounts are recorded. The uninsured patient accounts, net of contractual allowances recorded, are further reduced to their net realizable value at the time they are recorded through implicit price concessions based on historical collection trends for self-pay accounts and other factors that affect the estimation process. There are various factors that can impact collection trends, such as changes in the economy, which in turn have an impact on unemployment rates and the number of uninsured and underinsured patients, the volume of patients through our emergency departments, the increased burden of co-pays, co-insurance amounts and deductibles to be made by patients with insurance, and business practices related to collection efforts. These factors continuously change and can have an impact on collection trends and our estimation process. Subsequent changes to the estimate of the transaction price are generally recorded as adjustments to net patient service revenues in the period of the change. We have provided implicit price concessions, primarily to uninsured patients and patients with co-pays, co-insurance and deductibles. The implicit price concessions included in estimating the transaction price represent the difference between amounts billed to patients and the amounts we expect to collect based on our collection history with similar patients. Although outcomes vary, our policy is to attempt to collect amounts due from patients, including co-pays, co-insurance and deductibles due from patients with insurance, at the time of service while complying with all federal and state statutes and regulations, including, but not limited to, the Emergency Medical Treatment and Active Labor Act (“EMTALA”). Generally, as required by EMTALA, patients may not be denied emergency treatment due to inability to pay. Therefore, services, including the legally required medical screening examination and stabilization of the patient, are performed without delaying to obtain insurance information. In non-emergency circumstances or for elective procedures and services, it is our policy to verify insurance prior to a patient being treated; however, there are various exceptions that can occur. Such exceptions can include, for example, instances where (1) we are unable to obtain verification because the patient’s insurance company was unable to be reached or contacted, (2) a determination is made that a patient may be eligible for benefits under various government programs, such as Medicaid or Victims of Crime, and it takes several days or weeks before qualification for such benefits is confirmed or denied, and (3) under physician orders we provide services to patients that require immediate treatment. We also provide charity care to patients who are financially unable to pay for the healthcare services they receive. Most patients who qualify for charity care are charged a per-diem amount for services received, subject to a cap. Except for the per-diem amounts, our policy is not to pursue collection of amounts determined to qualify as charity care; therefore, we do not report these amounts in net operating revenues. Patient advocates from Conifer’s Medical Eligibility Program screen patients in the hospital to determine whether those patients meet eligibility requirements for financial assistance programs. They also expedite the process of applying for these government programs. Conifer Revenues— Our Conifer segment recognizes revenue from its contracts when Conifer’s performance obligations are satisfied, which is generally as services are rendered. Revenue is recognized in an amount that reflects the consideration to which Conifer expects to be entitled. At contract inception, Conifer assesses the services specified in its contracts with customers and identifies a performance obligation for each distinct contracted service. Conifer identifies the performance obligations and considers all the services provided under the contract. Conifer generally considers the following distinct services as separate performance obligations: • revenue cycle management services; • value-based care services; • patient communication and engagement services; • consulting services; and • other client-defined projects.
Electronic Health Record Incentives	Electronic Health Record Incentives Under certain provisions of the American Recovery and Reinvestment Act of 2009 (“ARRA”), federal incentive payments are available to hospitals, physicians and certain other professionals when they adopt, implement or upgrade (“AIU”) certified electronic health record (“EHR”) technology or become “meaningful users,” as defined under ARRA, of EHR technology in ways that demonstrate improved quality, safety and effectiveness of care. We recognize Medicaid EHR incentive payments in our consolidated statements of operations for the first payment year when: (1) CMS approves a state’s EHR incentive plan; and (2) our hospital or employed physician acquires certified EHR technology (i.e., when AIU criteria are met). Medicaid EHR incentive payments for subsequent payment years are recognized in the period during which the specified meaningful use criteria are met. We recognize Medicare EHR incentive payments when: (1) the specified meaningful use criteria are met; and (2) contingencies in estimating the amount of the incentive payments to be received are resolved. During the years ended December 31, 2018 , 2017 and 2016 , certain of our hospitals and physicians satisfied the CMS AIU and/or meaningful use criteria. As a result, we recognized $3 million , $9 million and $32 million of Medicare and Medicaid EHR incentive payments as a reduction to expense in the accompanying Consolidated Statement of Operations for the years ended December 31, 2018 , 2017 and 2016
Cash and Cash Equivalents	Cash and Cash Equivalents We treat highly liquid investments with original maturities of three months or less as cash equivalents. Cash and cash equivalents were $411 million and $611 million at December 31, 2018 and 2017 , respectively. At December 31, 2018 and 2017 , our book overdrafts were $288 million and $311 million , respectively, which were classified as accounts payable. At December 31, 2018 and 2017 , $177 million and $179 million , respectively, of total cash and cash equivalents in the accompanying Consolidated Balance Sheets were intended for the operations of our captive insurance subsidiaries, and $8 million and $30 million , respectively, of total cash and cash equivalents in the accompanying Consolidated Balance Sheets were intended for the operations of our health plan-related businesses. Also at December 31, 2018 and 2017 , we had $135 million and $117 million , respectively, of property and equipment purchases accrued for items received but not yet paid. Of these amounts, $114 million and $79 million , respectively, were included in accounts payable. During the years ended December 31, 2018 and 2017 , we recorded non-cancellable capital leases of $149 million and $162 million
Investments in Debt and Equity Securities	Investments in Debt and Equity Securities Prior to the adoption of ASU 2016-01 on January 1, 2018, we classified investments in debt and equity securities as either available-for-sale, held-to-maturity or as part of a trading portfolio. At December 31, 2017, we had no significant investments in securities classified as either held-to-maturity or trading. We carried securities classified as available-for-sale at fair value. We reported their unrealized gains and losses, net of taxes, as accumulated other comprehensive income (loss) unless we determined that a loss was other-than-temporary, at which point we would record a loss in our consolidated statements of operations. We included realized gains or losses in our consolidated statements of operations based on the specific identification method. Subsequent to the adoption of ASU 2016-01 on January 1, 2018, we classify investments in debt securities as either available-for-sale, held-to-maturity or as part of a trading portfolio, but these classifications are no longer applicable to equity securities. At December 31, 2018
Investments in Unconsolidated Affiliates	Investments in Unconsolidated Affiliates We control 227 of the facilities within our Ambulatory Care segment and, therefore, consolidate their results. We account for many of the facilities our Ambulatory Care segment operates ( 110 of 337 at December 31, 2018 ), as well as additional companies in which our Hospital Operations and other segment holds ownership interests, under the equity method as investments in unconsolidated affiliates and report only our share of net income as equity in earnings of unconsolidated affiliates in the accompanying Consolidated Statements of Operations. Summarized financial information for these equity method investees is included in the following table; among the equity method investees are four North Texas hospitals in which we held minority interests and that were operated by our Hospital Operations and other segment through the divestiture of these investments effective March 1, 2018. We recorded a gain of $11 million in the year ended December 31, 2018 due to the sales of our minority interest in these hospitals. For investments acquired during the reported periods, amounts reflect 100% of the investee’s results beginning on the date of our acquisition of the investment. December 31, 2018 December 31, 2017 December 31, 2016 Current assets $ 842 $ 805 $ 943 Noncurrent assets $ 662 $ 1,223 $ 991 Current liabilities $ (313 ) $ (354 ) $ (320 ) Noncurrent liabilities $ (430 ) $ (389 ) $ (345 ) Noncontrolling interests $ (530 ) $ (490 ) $ (494 ) Years Ended December 31, 2018 2017 2016 Net operating revenues $ 2,469 $ 2,907 $ 2,823 Net income $ 599 $ 558 $ 573 Net income attributable to the investees $ 372 $ 363 $ 343 Our equity method investment that contributes the most to our equity in earnings of unconsolidated affiliates is Texas Health Ventures Group, LLC (“THVG”), which is operated by USPI. THVG represented $70 million of the total $150 million equity in earnings of unconsolidated affiliates we recognized for the year ended December 31, 2018 , $69 million of the total $144 million equity in earnings of unconsolidated affiliates we recognized for the year ended December 31, 2017 and $61 million of the total $131 million equity in earnings of unconsolidated affiliates we recognized for the year ended December 31, 2016
Property and Equipment	Property and Equipment Additions and improvements to property and equipment exceeding established minimum amounts with a useful life greater than one year are capitalized at cost. Expenditures for maintenance and repairs are charged to expense as incurred. We use the straight-line method of depreciation for buildings, building improvements and equipment. The estimated useful life for buildings and improvements is primarily 15 to 40 years, and for equipment three to 15 years. Newly constructed hospitals are usually depreciated over 50 years. We record capital leases at the beginning of the lease term as assets and liabilities. The value recorded is the lower of either the present value of the minimum lease payments or the fair value of the asset. Such assets, including improvements, are generally amortized over the shorter of either the lease term or their estimated useful life. Interest costs related to construction projects are capitalized. In the years ended December 31, 2018 , 2017 and 2016 , capitalized interest was $7 million , $15 million and $22 million , respectively. We evaluate our long-lived assets for possible impairment annually or whenever events or changes in circumstances indicate that the carrying amount of the asset, or related group of assets, may not be recoverable from estimated future undiscounted cash flows. If the estimated future undiscounted cash flows are less than the carrying value of the assets, we calculate the amount of an impairment if the carrying value of the long-lived assets exceeds the fair value of the assets. The fair value of the assets is estimated based on appraisals, established market values of comparable assets or internal estimates of future net cash flows expected to result from the use and ultimate disposition of the asset. The estimates of these future cash flows are based on assumptions and projections we believe to be reasonable and supportable. They require our subjective judgments and take into account assumptions about revenue and expense growth rates. These assumptions may vary by type of facility and presume stable, improving or, in some cases, declining results at our hospitals, depending on their circumstances.
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets Goodwill represents the excess of costs over the fair value of assets of businesses acquired. Goodwill and other intangible assets acquired in purchase business combinations and determined to have indefinite useful lives are not amortized, but instead are subject to impairment tests performed at least annually. For goodwill, we perform the test at the reporting unit level when events occur that require an evaluation to be performed or at least annually. If we determine the carrying value of goodwill is impaired, or if the carrying value of a business that is to be sold or otherwise disposed of exceeds its fair value, we reduce the carrying value, including any allocated goodwill, to fair value. Estimates of fair value are based on appraisals, established market prices for comparable assets or internal estimates of future net cash flows and presume stable, improving or, in some cases, declining results at our hospitals, depending on their circumstances. Other intangible assets primarily consist of capitalized software costs, which are amortized on a straight-line basis over the estimated useful life of the software, which ranges from three to 15
Accruals for General and Professional Liability Risks	Accruals for General and Professional Liability Risks We accrue for estimated professional and general liability claims, when they are probable and can be reasonably estimated. The accrual, which includes an estimate for incurred but not reported claims, is updated each quarter based on a model of projected payments using case-specific facts and circumstances and our historical loss reporting, development and settlement patterns and is discounted to its net present value using a risk-free discount rate of 2.59% at December 31, 2018 and 2.33% at December 31, 2017
Income Taxes	Income Taxes We account for income taxes using the asset and liability method. This approach requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the carrying amounts and the tax bases of assets and liabilities. Income tax receivables and liabilities and deferred tax assets and liabilities are recognized based on the amounts that more likely than not will be sustained upon ultimate settlement with taxing authorities. Developing our provision for income taxes and analysis of uncertain tax positions requires significant judgment and knowledge of federal and state income tax laws, regulations and strategies, including the determination of deferred tax assets and liabilities and, if necessary, any valuation allowances that may be required for deferred tax assets. We assess the realization of our deferred tax assets to determine whether an income tax valuation allowance is required. Based on all available evidence, both positive and negative, and the weight of that evidence to the extent such evidence can be objectively verified, we determine whether it is more likely than not that all or a portion of the deferred tax assets will be realized. The main factors that we consider include: • Cumulative profits/losses in recent years, adjusted for certain nonrecurring items; • Income/losses expected in future years; • Unsettled circumstances that, if unfavorably resolved, would adversely affect future operations and profit levels; • The availability, or lack thereof, of taxable income in prior carryback periods that would limit realization of tax benefits; and • The carryforward period associated with the deferred tax assets and liabilities. We consider many factors when evaluating our uncertain tax positions, and such judgments are subject to periodic review. Tax benefits associated with uncertain tax positions are recognized in the period in which one of the following conditions is satisfied: (1) the more likely than not recognition threshold is satisfied; (2) the position is ultimately settled through negotiation or litigation; or (3) the statute of limitations for the taxing authority to examine and challenge the position has expired. Tax benefits associated with an uncertain tax position are derecognized in the period in which the more likely than not recognition threshold is no longer satisfied.
Segment Reporting	Segment Reporting We primarily operate acute care hospitals and related healthcare facilities. Our Hospital Operations and other segment generated 80% , 82% and 83% of our net operating revenues net of implicit price concessions and provision for doubtful accounts in the years ended December 31, 2018 , 2017 and 2016 , respectively. At December 31, 2018 , each of our markets related to our general hospitals reported directly to our president of hospital operations. Major decisions, including capital resource allocations, are made at the consolidated level, not at the market or hospital level. Our Hospital Operations and other segment is comprised of our acute care and specialty hospitals, ancillary outpatient facilities, urgent care centers, microhospitals and physician practices. As described in Note 5 , certain of our facilities were classified as held for sale in the accompanying Consolidated Balance Sheet at December 31, 2018 . Our Ambulatory Care segment is comprised of the operations of USPI and included nine Aspen facilities in the United Kingdom until their divestiture effective August 17, 2018. Our Conifer segment provides healthcare business process services in the areas of hospital and physician revenue cycle management and value-based care solutions to healthcare systems, as well as individual hospitals, physician practices, self-insured organizations, health plans and other entities
Costs Associated With Exit or Disposal Activities	Costs Associated With Exit or Disposal Activities
Recent Accounting Standards	Recently Issued Accounting Standards In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)” (“ASU 2016-02”), which affects any entity that enters into a lease (as that term is defined in ASU 2016-02), with some specified scope exceptions. The main difference between the guidance in ASU 2016-02 and current GAAP is the recognition of lease assets and lease liabilities by lessees for those leases classified as operating leases under current GAAP. Under ASU 2016-02, lessees and lessors are required to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach, which includes a number of optional practical expedients. In July 2018, the FASB issued ASU 2018-11 “Leases (Topic 842) Targeted Improvements,” which allows lessees and lessors to recognize and measure leases at the beginning of the period of adoption without modifying the comparative period financial statements. This guidance will be effective for us beginning in 2019, and we intend to use the retrospective method as of the period of adoption rather than the earliest period presented meaning that our financial statements for periods prior to January 1, 2019 will not be modified for the application of the new lease accounting standard. We will elect the three packaged transition practical expedients under ASC 842-10-65-1(f) and the practical expedient that allows lessees to choose to not separate lease and non-lease components by class of underlying asset. We expect that, as of January 1, 2019, our consolidated assets and liabilities will both increase by approximately $750 million to $800 million related to on-balance sheet recognition of right of use assets and liabilities. Right of use assets associated with operating leases will be included as an intangible asset, and liabilities associated with operating leases will be split between our other current liabilities and other long-term liabilities in our consolidated balance sheets. We are still finalizing our calculation of the cumulative effect of accounting change we will recognize upon adoption. We are currently working to complete the implementation of new processes and information technology tools to assist in our ongoing lease data collection and analysis, and updating our accounting policies and internal controls in connection with the adoption of the new standard. In August 2018, the FASB issued ASU 2018-13, “Fair Value Measurement (Topic 820) Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement” (“ASU 2018-13”), which applies to all entities that are required to make disclosures about recurring or nonrecurring fair value measurements. The amendments in ASU 2018-13, which remove, modify or add certain disclosure requirements as part of the FASB’s disclosure framework project to improve the effectiveness of the notes to the financial statements, are effective for us beginning in 2020. The adoption of this guidance will not impact our financial position, results of operations or cash flows. Also in August 2018, the FASB issued ASU 2018-14, “Compensation – Retirement Benefits – Defined Benefit Plans –General (Subtopic 715-20) Disclosure Framework—Changes to the Disclosure Requirements for Defined Benefit Plans” (“ASU 2018-14”), which applies to all employers that sponsor defined benefit pension or other postretirement plans. The amendments in ASU 2018-14, which remove, modify or add certain disclosure requirements as part of the FASB’s disclosure framework project to improve the effectiveness of the notes to the financial statements, are effective for us beginning in 2021. The adoption of this guidance will not impact our financial position, results of operations or cash flows. Additionally, the FASB issued ASU 2018-15, “Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-40) Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract” (“ASU 2018-14”), which applies to all entities that are a customer in a hosting arrangement that is a service contract. The amendments in ASU 2018-14, which align the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software, are effective for us beginning in 2020. We do not expect adoption of this guidance to have a material effect on our financial position, results of operations or cash flows. Recently Adopted Accounting Standards Effective January 1, 2018, as further discussed in Note 1, we adopted ASU 2014-09 and ASU 2016-01, and we early adopted ASU 2018-02. Also effective January 1, 2018, we adopted ASU 2016-15, “Statement of Cash Flows (Topic 230) Classification of Certain Cash Receipts and Cash Payments” and ASU 2016-18, “Statement of Cash Flows (Topic 230) Restricted Cash,” both of which were applied using a retrospective transition method to each period presented and did not have any effect on our statements of cash flows. Effective January 1, 2017, as further discussed in Note 1, we adopted ASU 2016-09 and early adopted ASU 2017-07. We also early adopted ASU 2017-04, “Intangibles – Goodwill and Other (Topic 350)” (“ASU 2017‑04”) for our annual goodwill impairment tests for the year ended December 31, 2017. The amendments in ASU 2017-04 modified the concept of impairment from the condition that exists when the carrying amount of goodwill exceeds its implied fair value to the condition that exists when the carrying amount of a reporting unit exceeds its fair value. An entity no longer determines goodwill

SIGNIFICANT ACCOUNTING POLICI_3

SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Schedule of Equity Method Investments	For investments acquired during the reported periods, amounts reflect 100% of the investee’s results beginning on the date of our acquisition of the investment. December 31, 2018 December 31, 2017 December 31, 2016 Current assets $ 842 $ 805 $ 943 Noncurrent assets $ 662 $ 1,223 $ 991 Current liabilities $ (313 ) $ (354 ) $ (320 ) Noncurrent liabilities $ (430 ) $ (389 ) $ (345 ) Noncontrolling interests $ (530 ) $ (490 ) $ (494 ) Years Ended December 31, 2018 2017 2016 Net operating revenues $ 2,469 $ 2,907 $ 2,823 Net income $ 599 $ 558 $ 573 Net income attributable to the investees $ 372 $ 363 $ 343

ACCOUNTS RECEIVABLE (Tables)

ACCOUNTS RECEIVABLE (Tables)	12 Months Ended
	Dec. 31, 2018
Accounts Receivable Additional Disclosures [Abstract]
Schedule of Components of Accounts Receivable	The principal components of accounts receivable are shown in the table below: December 31, 2018 December 31, 2017 Continuing operations: Patient accounts receivable $ 2,427 $ 3,376 Allowance for doubtful accounts — (898 ) Estimated future recoveries 148 132 Net cost reports and settlements payable and valuation allowances 18 4 2,593 2,614 Discontinued operations 2 2 Accounts receivable, net $ 2,595 $ 2,616
Schedule of Estimated Costs for Charity Care and Self-Pay Patients	The table below shows our estimated costs of caring for our self-pay patients and charity care patients, as well as revenues attributable to Medicaid DSH and other supplemental revenues we recognized in the years ended December 31, 2018 , 2017 and 2016 . Years Ended December 31, 2018 2017 2016 Estimated costs for: Self-pay patients $ 640 $ 648 $ 609 Charity care patients 124 121 138 Total $ 764 $ 769 $ 747 Medicaid DSH and other supplemental revenues $ 847 $ 864 $ 906

CONTRACT BALANCES (Tables)

CONTRACT BALANCES (Tables)	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Opening and Closing Balances of Contracts Assets and Liabilities	The opening and closing balances of Conifer’s receivables, contract asset, and current and long-term contract liabilities are as follows: Contract Liability- Contract Liability- Contract Asset- Current Long-Term Receivables Unbilled Revenue Deferred Revenue Deferred Revenue January 1, 2018 $ 89 $ 10 $ 80 $ 21 December 31, 2018 42 11 61 20 Increase/(decrease) $ (47 ) $ 1 $ (19 ) $ (1 ) January 1, 2017 $ 67 $ 8 $ 76 $ 26 December 31, 2017 89 10 80 21 Increase/(decrease) $ 22 $ 2 $ 4 $ (5 ) 2018 2017 January 1, $ 171 $ — December 31, 169 — Increase/(decrease) $ (2 ) $ —

ASSETS AND LIABILITIES HELD F_2

ASSETS AND LIABILITIES HELD FOR SALE (Tables)	12 Months Ended
	Dec. 31, 2018
Discontinued Operation, Additional Disclosures [Abstract]
Assets and Liabilities Classified as Held for Sale and Components of Business that have Been Disposed of or have Been Classified as Held for Sale	Assets and liabilities classified as held for sale at December 31, 2018 were comprised of the following: Accounts receivable $ 54 Other current assets 13 Investments and other long-term assets 1 Property and equipment 39 Current liabilities (36 ) Long-term liabilities (7 ) Net assets held for sale $ 64 Years Ended December 31, 2018 2017 2016 Significant disposals: Income (loss) from continuing operations, before income taxes Houston (includes a $111 million gain on sale in the 2017 period) $ (10 ) $ 133 $ 67 Philadelphia (includes $232 million of impairment charges in the 2017 period) $ (29 ) $ (255 ) $ (75 ) MacNeal (includes a $90 million gain on sale in the 2018 period) 93 27 29 Aspen (includes $59 million of impairment charges in the 2017 period) $ (6 ) $ (68 ) $ (16 ) Total 48 (163 ) 5 Significant planned divestitures classified as held for sale: Loss from continuing operations, before income taxes Chicago area (includes $24 million of impairment charges in the 2018 period and $73 million in the 2017 period) (41 ) (82 ) (1 ) Total $ (41 ) $ (82 ) $ (1 )

LONG-TERM DEBT AND LEASE OBLI_2

LONG-TERM DEBT AND LEASE OBLIGATIONS (Tables)	12 Months Ended
	Dec. 31, 2018
Long-term Debt and Capital Lease Obligations [Abstract]
Summary of Long-Term Debt	The table below shows our long-term debt as of December 31, 2018 and 2017 : December 31, 2018 December 31, 2017 Senior unsecured notes: 5.500% due 2019 $ 468 $ 500 6.750% due 2020 300 300 8.125% due 2022 2,800 2,800 6.750% due 2023 1,872 1,900 7.000% due 2025 478 500 6.875% due 2031 362 430 Senior secured first lien notes: 4.750% due 2020 500 500 6.000% due 2020 1,800 1,800 4.500% due 2021 850 850 4.375% due 2021 1,050 1,050 4.625% due 2024 1,870 1,870 Senior secured second lien notes: 7.500% due 2022 750 750 5.125% due 2025 1,410 1,410 Capital leases 425 431 Mortgage notes 75 77 Unamortized issue costs, note discounts and premiums (184 ) (231 ) Total long-term debt 14,826 14,937 Less current portion 182 146 Long-term debt, net of current portion $ 14,644 $ 14,791
Schedule of Future Long Term Debt Maturities and Minimum Operating Lease Payments	Future long-term debt maturities and minimum operating lease payments as of December 31, 2018 are as follows: Years Ending December 31, Later Years Total 2019 2020 2021 2022 2023 Long-term debt, including capital lease obligations $ 15,010 $ 182 $ 2,697 $ 1,958 $ 3,588 $ 1,894 $ 4,691 Long-term non-cancelable operating leases $ 932 $ 171 $ 151 $ 133 $ 113 $ 92 $ 272

EMPLOYEE BENEFIT PLANS (Tables)

EMPLOYEE BENEFIT PLANS (Tables)	12 Months Ended
	Dec. 31, 2018
Defined Benefit Plan [Abstract]
Schedule of Information Related to Stock-Based Awards by Grant Date	The table below shows certain stock option and restricted stock unit grants and other awards that comprise the stock-based compensation expense recorded in the year ended December 31, 2018 . Compensation cost is measured by the fair value of the awards on their grant dates and is recognized over the requisite service period of the awards, whether or not the awards had any intrinsic value during the period. Grant Date Awards Exercise Price Per Share Fair Value Per Share at Grant Date Stock-Based Compensation Expense for Year Ended December 31, 2018 (In Thousands) (In Millions) Stock Options: February 28, 2018 593 $ 20.60 $ 8.83 $ 2 September 29, 2017 409 $ 16.43 $ 5.63 2 March 1, 2017 877 $ 18.99 $ 8.52 1 Restricted Stock Units: June 28, 2018 51 $ 34.61 1 May 4, 2018 54 $ 23.53 1 March 29, 2018 293 $ 24.25 3 February 28, 2018 272 $ 20.60 2 March 1, 2017 404 $ 18.99 2 June 30, 2016 113 $ 27.64 1 May 31, 2016 54 $ 28.94 1 March 10, 2016 566 $ 25.50 3 February 25, 2015 1,374 $ 45.63 1 August 25, 2014 460 $ 59.90 4 Other grants 4 USPI Management Equity Plan 18 $ 46
Summary of Stock Option Activity	The following table summarizes stock option activity during the years ended December 31, 2018 , 2017 and 2016 : Options Weighted Average Exercise Price Per Share Aggregate Intrinsic Value Weighted Average Remaining Life (In Millions) Outstanding at December 31, 2015 1,606,842 $ 22.87 Granted — — Exercised (111,715 ) 17.88 Forfeited/Expired (59,206 ) 18.68 Outstanding at December 31, 2016 1,435,921 $ 22.87 Granted 1,396,307 18.24 Exercised (20,400 ) 4.56 Forfeited/Expired (247,006 ) 24.37 Outstanding at December 31, 2017 2,564,822 $ 20.35 Granted 635,196 21.33 Exercised (619,849 ) 18.19 Forfeited/Expired (317,426 ) 35.30 Outstanding at December 31, 2018 2,262,743 $ 19.12 $ 1 6.7 years Vested and expected to vest at December 31, 2018 2,262,743 $ 19.12 $ 1 6.7 years Exercisable at December 31, 2018 767,037 $ 17.47 $ 1 3.2 years
Schedule of Assumptions Used to Determine Fair Value of Stock Options	These fair values were calculated based on each grant date, using a Monte Carlo simulation with the following assumptions: February 28, September 29, March 1, 2018 2017 2017 Expected volatility 46% 46% 49% Expected dividend yield 0% 0% 0% Expected life 6.2 years 3.0 years 6.2 years Expected forfeiture rate 0% 0% 0% Risk-free interest rate 2.72% 1.92% 2.15%
Summary of Information About Stock Options by Range of Exercise Prices	The following table summarizes information about our outstanding stock options at December 31, 2018 : Options Outstanding Options Exercisable Range of Exercise Prices Number of Options Weighted Average Remaining Contractual Life Weighted Average Exercise Price Number of Options Weighted Average Exercise Price $0.00 to $4.569 82,409 0.2 years $ 4.56 82,409 $ 4.56 $4.57 to $19.759 1,285,795 6.7 years $ 18.18 413,960 $ 16.46 $19.76 to $35.430 894,539 7.4 years $ 21.83 270,668 $ 22.94 2,262,743 6.7 years $ 19.12 767,037 $ 17.47
Schedule of Stock Options by Monetary Status and Employment Status of the Awardees	21.7% were in-the-money, that is, they had exercise price less than the $17.14 market price of our common stock on December 31, 2018 , and 78.3% were out-of-the-money, that is, they had an exercise price of more than $17.14 as shown in the table below: In-the-Money Options Out-of-the-Money Options All Options Outstanding % of Total Outstanding % of Total Outstanding % of Total Current employees 469,849 95.7 % 1,147,105 64.7 % 1,616,954 71.5 % Former employees 21,086 4.3 % 624,703 35.3 % 645,789 28.5 % Totals 490,935 100.0 % 1,771,808 100.0 % 2,262,743 100.0 % % of all outstanding options 21.7 % 78.3 % 100.0 %
Summary of Restricted Stock Unit Activity	The following table summarizes restricted stock unit activity during the years ended December 31, 2018 , 2017 and 2016 : Restricted Stock Units Weighted Average Grant Date Fair Value Per Unit Unvested at December 31, 2015 3,627,232 $ 44.69 Granted 1,626,329 30.05 Vested (1,644,616 ) 42.95 Forfeited (434,412 ) 38.59 Unvested at December 31, 2016 3,174,533 $ 38.75 Granted 714,018 18.25 Vested (1,397,953 ) 35.50 Forfeited (236,610 ) 32.13 Unvested at December 31, 2017 2,253,988 $ 35.20 Granted 765,184 24.74 Vested (995,331 ) 32.63 Forfeited (139,711 ) 36.01 Unvested at December 31, 2018 1,884,130 $ 32.25
Schedule of Employee Stock Purchase Plan Activity	We sold the following numbers of shares under our employee stock purchase plan in the years ended December 31, 2018 , 2017 and 2016 : Years Ended December 31, 2018 2017 2016 Number of shares 228,045 395,957 217,184 Weighted average price $ 22.96 $ 17.28 $ 17.21
Schedule of Reconciliation of Funded Status of Plans, the Amounts included in the Consolidated Balance Sheets and Assumptions Used for Projected Benefit Obligations	The following tables summarize the balance sheet impact, as well as the benefit obligations, funded status and rate assumptions associated with the SERPs and the DMC Pension Plan based on actuarial valuations prepared as of December 31, 2018 and 2017 : December 31, 2018 2017 Reconciliation of funded status of plans and the amounts included in the Consolidated Balance Sheets: Projected benefit obligations (1) Beginning obligations $ (1,455 ) $ (1,475 ) Service cost (2 ) (2 ) Interest cost (56 ) (62 ) Actuarial gain (loss) 90 (31 ) Benefits paid 122 120 Special termination benefit costs — (5 ) Ending obligations (1,301 ) (1,455 ) Fair value of plans assets Beginning plan assets 850 786 Gain (loss) on plan assets (65 ) 122 Employer contribution 47 43 Benefits paid (101 ) (101 ) Ending plan assets 731 850 Funded status of plans $ (570 ) $ (605 ) Amounts recognized in the Consolidated Balance Sheets consist of: Other current liability $ (49 ) $ (69 ) Other long-term liability $ (521 ) $ (536 ) Accumulated other comprehensive loss $ 281 $ 266 SERP Assumptions: Discount rate 4.50 % 3.75 % Compensation increase rate 3.00 % 3.00 % Measurement date December 31, 2018 December 31, 2017 DMC Pension Plan Assumptions: Discount rate 4.62 % 4.00 % Compensation increase rate Frozen Frozen Measurement date December 31, 2018 December 31, 2017 (1) The accumulated benefit obligation at December 31, 2018 and 2017 was approximately $1.299 billion and $1.448 billion
Schedule of Components of Net Benefit Costs and Assumptions Used for Net Periodic Benefit Costs	The components of net periodic benefit costs and related assumptions are as follows: Years Ended December 31, 2018 2017 2016 Service costs $ 2 $ 2 $ 2 Interest costs 56 62 69 Expected return on plan assets (54 ) (50 ) (51 ) Amortization of net actuarial loss 14 14 12 Net periodic benefit cost $ 18 $ 28 $ 32 SERP Assumptions: Discount rate 3.75 % 4.25 % 4.75 % Long-term rate of return on assets n/a n/a n/a Compensation increase rate 3.00 % 3.00 % 3.00 % Measurement date January 1, 2018 January 1, 2017 January 1, 2016 Census date January 1, 2018 January 1, 2017 January 1, 2016 DMC Pension Plan Assumptions: Discount rate 4.00 % 4.42 % 4.67 % Long-term rate of return on assets 6.50 % 6.50 % 6.50 % Compensation increase rate Frozen Frozen Frozen Measurement date January 1, 2018 January 1, 2017 January 1, 2016 Census date January 1, 2018 January 1, 2017 January 1, 2016
Schedule of Weighted-Average Asset Allocations by Asset Category	The weighted-average asset allocations by asset category as of December 31, 2018 , were as follows: Asset Category Target Actual Cash and cash equivalents 2 % 2 % U.S. government obligations — % 2 % Equity securities 64 % 65 % Debt securities 34 % 31 % Alternative investments 1 % 1 %
Summary of DMC Pension Plan Assets Measured at Fair Value on a Recurring Basis Aggregated by the Level in the Fair Value Hierarchy	The following tables summarize the DMC Pension Plan assets measured at fair value on a recurring basis as of December 31, 2018 and 2017 , aggregated by the level in the fair value hierarchy within which those measurements are determined. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities. We consider a security that trades at least weekly to have an active market. Fair values determined by Level 2 inputs utilize data points that are observable, such as quoted prices for similar assets, interest rates and yield curves. Fair values determined by Level 3 inputs are unobservable data points for the asset or liability, and include situations where there is little, if any, market activity for the asset or liability. December 31, 2018 Level 1 Level 2 Level 3 Cash and cash equivalents $ 33 $ 33 $ — $ — U.S. government obligations 9 9 — — Equity securities 423 423 — — Fixed income funds 262 262 — — Futures contracts 4 4 — — $ 731 $ 731 $ — $ — December 31, 2017 Level 1 Level 2 Level 3 Cash and cash equivalents $ 49 $ 49 $ — $ — U.S. government obligations 5 5 — — Equity securities 488 488 — — Fixed income funds 308 308 — — $ 850 $ 850 $ — $ —
Schedule of Estimated Future Benefit Payments	The following table presents the estimated future benefit payments to be made from the SERPs and the DMC Pension Plan, a portion of which will be funded from plan assets, for the next five years and in the aggregate for the five years thereafter: Years Ending December 31, Five Years Total 2019 2020 2021 2022 2023 Thereafter Estimated benefit payments $ 897 $ 86 $ 89 $ 90 $ 91 $ 91 $ 450

PROPERTY AND EQUIPMENT (Tables)

PROPERTY AND EQUIPMENT (Tables)	12 Months Ended
	Dec. 31, 2018
Property, Plant and Equipment [Abstract]
Schedule of Components of Property and Equipment	The principal components of property and equipment are shown in the table below: December 31, 2018 2017 Land $ 613 $ 602 Buildings and improvements 6,920 6,837 Construction in progress 199 109 Equipment 4,482 4,221 12,214 11,769 Accumulated depreciation and amortization (5,221 ) (4,739 ) Net property and equipment $ 6,993 $ 7,030

GOODWILL AND OTHER INTANGIBLE_2

GOODWILL AND OTHER INTANGIBLE ASSETS (Tables)	12 Months Ended
	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Changes in the Carrying Amount of Goodwill	2018 2017 Ambulatory Care As of January 1: Goodwill $ 3,437 $ 3,447 Accumulated impairment losses — — Total 3,437 3,447 Goodwill acquired during the year and purchase price allocation adjustments 219 86 Goodwill related to assets held for sale and disposed or deconsolidated facilities 40 (103 ) Impact of foreign currency translation — 7 Total $ 3,696 $ 3,437 As of December 31: Goodwill $ 3,696 $ 3,437 Accumulated impairment losses — — Total $ 3,696 $ 3,437 2018 and 2017 : 2018 2017 Hospital Operations and other As of January 1: Goodwill $ 5,406 $ 5,803 Accumulated impairment losses (2,430 ) (2,430 ) Total 2,976 3,373 Goodwill acquired during the year and purchase price allocation adjustments 1 5 Goodwill related to assets held for sale and disposed or deconsolidated facilities 3 (402 ) Total $ 2,980 $ 2,976 As of December 31: Goodwill $ 5,410 $ 5,406 Accumulated impairment losses (2,430 ) (2,430 ) Total $ 2,980 $ 2,976 2018 2017 Conifer As of January 1: Goodwill $ 605 $ 605 Accumulated impairment losses — — Total 605 605 Goodwill acquired during the year and purchase price allocation adjustments — — Total $ 605 $ 605 As of December 31: Goodwill $ 605 $ 605 Accumulated impairment losses — — Total $ 605 $ 605
Schedule of Other Intangible Assets	The following table provides information regarding other intangible assets, which are included in the accompanying Consolidated Balance Sheets as of 2018 and 2017 : Gross Carrying Amount Accumulated Amortization Net Book Value At December 31, 2018: Capitalized software costs $ 1,667 $ (858 ) $ 809 Trade names 102 — 102 Contracts 871 (76 ) 795 Other 104 (79 ) 25 Total $ 2,744 $ (1,013 ) $ 1,731 At December 31, 2017: Capitalized software costs $ 1,582 $ (754 ) $ 828 Trade Names 102 — 102 Contracts 859 (60 ) 799 Other 106 (69 ) 37 Total $ 2,649 $ (883 ) $ 1,766
Schedule of Estimated Future Amortization of Intangibles with Finite Useful Lives	Estimated future amortization of intangibles with finite useful lives as of December 31, 2018 is as follows: Total Years Ending December 31, Later Years 2019 2020 2021 2022 2023 Amortization of intangible assets $ 1,053 $ 147 $ 131 $ 112 $ 99 $ 85 $ 479 We recognized amortization expense of $185 million , $172 million and $152 million in the accompanying Consolidated Statements of Operations for the years ended December 31, 2018 , 2017 and 2016

INVESTMENTS AND OTHER ASSETS (T

INVESTMENTS AND OTHER ASSETS (Tables)	12 Months Ended
	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Schedule of Investments and Other Assets	The principal components of investments and other assets in the accompanying Consolidated Balance Sheets are as follows: December 31, 2018 2017 Marketable securities $ 40 $ 56 Equity investments in unconsolidated healthcare entities 956 958 Total investments 996 1,014 Cash surrender value of life insurance policies 30 32 Long-term deposits 44 37 California provider fee program receivables 231 266 Land held for expansion, other long-term receivables and other assets 155 194 Investments and other assets $ 1,456 $ 1,543

ACCUMULATED OTHER COMPREHENSI_2

ACCUMULATED OTHER COMPREHENSIVE LOSS (Tables)	12 Months Ended
	Dec. 31, 2018
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Schedule of Accumulated Other Comprehensive Loss	Our accumulated other comprehensive loss is comprised of the following: December 31, 2018 2017 Adjustments for defined benefit plans $ (223 ) $ (170 ) Foreign currency translation adjustments — (38 ) Unrealized gains on investments $ — $ 4 Accumulated other comprehensive loss $ (223 ) $ (204 )

NET OPERATING REVENUES - (Table

NET OPERATING REVENUES - (Tables)	12 Months Ended
	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Sources of Net Operating Revenues Less Provisions for Doubtful Accounts and Implicit Price Concessions	The table below shows the composition of net operating revenues for our Conifer segment: Years Ended December 31, 2018 2017 2016 Revenue cycle services – Tenet $ 568 $ 583 $ 596 Revenue cycle services – other customers 855 891 839 Other services – Tenet 22 35 55 Other services – other customers 88 88 81 Total revenues from client contracts $ 1,533 $ 1,597 $ 1,571 Years Ended December 31, 2018 2017 2016 Net patient service revenues $ 1,965 $ 1,816 $ 1,684 Management fees 92 93 89 Revenue from other sources 28 31 24 Net operating revenues $ 2,085 $ 1,940 $ 1,797 Years Ended December 31, 2018 2017 2016 Hospital Operations and other: Net patient service revenues from hospitals and related Medicare $ 2,882 $ 3,243 $ 3,386 Medicaid 1,294 1,304 1,346 Managed care 9,213 9,583 9,728 Self-pay 96 91 63 Indemnity and other 596 608 604 Total 14,081 14,829 15,127 Physician practices revenues 1,097 1,209 1,201 Health plans 14 110 482 Revenue from other sources 93 112 94 Hospital Operations and other total prior to 15,285 16,260 16,904 Ambulatory Care 2,085 1,940 1,797 Conifer 1,533 1,597 1,571 Inter-segment eliminations (590 ) (618 ) (651 ) Net operating revenues $ 18,313 $ 19,179 $ 19,621
Revenue Expected to be Recognized in the Future Related to Performance Obligations	The following table includes Conifer’s revenue that is expected to be recognized in the future related to performance obligations that are unsatisfied, or partially unsatisfied, at the end of the reporting period. The amounts in the table primarily consist of revenue cycle management fixed fees, which are typically recognized ratably as the performance obligation is satisfied. The estimated revenue does not include volume or contingency based contracts, performance incentives, penalties or other variable consideration that is considered constrained. Conifer’s contract with Catholic Health Initiatives (“CHI”), a minority interest owner of Conifer Health Solutions, LLC, represents the majority of the fixed-fee revenue related to remaining performance obligations. Conifer’s contract term with CHI ends in 2032. Years Ending December 31, Later Years Total 2019 2020 2021 2022 2023 Performance obligations $ 7,736 $ 585 $ 584 $ 581 $ 581 $ 581 $ 4,824

CLAIMS AND LAWSUITS (Tables)

CLAIMS AND LAWSUITS (Tables)	12 Months Ended
	Dec. 31, 2018
Commitments and Contingencies Disclosure [Abstract]
Reconciliations Of Legal Settlements And Related Costs	The following table presents reconciliations of the beginning and ending liability balances in connection with legal settlements and related costs recorded in continuing operations during the years ended December 31, 2018 , 2017 and 2016 . No amounts were recorded in discontinued operations in the 2018, 2017 and 2016 periods. Balances at Beginning of Period Litigation and Investigation Costs Cash Payments Other Balances at End of Period Year Ended December 31, 2018 $ 12 $ 38 $ (41 ) $ (1 ) $ 8 Year Ended December 31, 2017 $ 12 $ 23 $ (23 ) $ — $ 12 Year Ended December 31, 2016 $ 299 $ 293 $ (582 ) $ 2 $ 12

REDEEMABLE NONCONTROLLING INT_2

REDEEMABLE NONCONTROLLING INTERESTS IN EQUITY OF CONSOLIDATED SUBSIDIARIES (Tables)	12 Months Ended
	Dec. 31, 2018
Noncontrolling Interest [Abstract]
Schedule of Changes in Redeemable Noncontrolling Interests in Equity of Consolidated Subsidiaries	The following table shows the changes in redeemable noncontrolling interests in equity of consolidated subsidiaries during the years ended 2018 and 2017 : December 31, 2018 2017 Balances at beginning of period $ 1,866 $ 2,393 Net income 190 239 Distributions paid to noncontrolling interests (142 ) (128 ) Accretion of redeemable noncontrolling interests 173 33 Purchases and sales of businesses and noncontrolling interests, net (667 ) (671 ) Balances at end of period $ 1,420 $ 1,866

INCOME TAXES (Tables)

INCOME TAXES (Tables)	12 Months Ended
	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Schedule of Provision for Income Taxes For Continuing Operations	The provision for income taxes for continuing operations for the years ended December 31, 2018 , 2017 and 2016 consists of the following: Years Ended December 31, 2018 2017 2016 Current tax expense (benefit): Federal $ (6 ) $ (4 ) $ 12 State 33 23 14 27 19 26 Deferred tax expense (benefit): Federal 159 202 34 State (10 ) (2 ) 7 149 200 41 $ 176 $ 219 $ 67
Schedule of Reconciliation Between Reported Income Tax Expense (Benefit) and Income Taxes Calculated by the Statutory Federal Income Tax Rate	A reconciliation between the amount of reported income tax expense and the amount computed by multiplying income (loss) from continuing operations before income taxes by the statutory federal income tax rate is shown below. State income tax expense for the year ended December 31, 2018 includes $9 million of expense related to the write off of expired or worthless unutilized state net operating loss carryforwards and other deferred tax assets for which a full valuation allowance had been provided in prior years. A corresponding tax benefit of $9 million is included for the year ended December 31, 2018 to reflect the reduction in the valuation allowance. Foreign pre-tax loss for the years ended December 31, 2018 and 2017 was $6 million and $70 million , respectively. Years Ended December 31, 2018 2017 2016 Tax expense (benefit) at statutory federal rate of 21% in 2018 $ 134 $ (35 ) $ 87 State income taxes, net of federal income tax benefit 23 4 16 Expired state net operating losses, net of federal income tax benefit 9 28 35 Tax attributable to noncontrolling interests (70 ) (113 ) (106 ) Nondeductible goodwill 8 109 29 Nontaxable gains — — (11 ) Nondeductible litigation costs — — 37 Impact of decrease in federal tax rate on deferred taxes (1 ) 246 — Reversal of permanent reinvestment assumption and other adjustments (6 ) (30 ) — Stock-based compensation tax deficiencies 5 15 — Changes in valuation allowance (including impact of decrease in federal tax rate) 76 — (25 ) Change in tax contingency reserves, including interest (1 ) (6 ) (9 ) Prior-year provision to return adjustments and other changes in deferred taxes (5 ) 4 12 Other items 4 (3 ) 2 Income tax expense $ 176 $ 219 $ 67
Schedule of Components of Deferred Tax Assets and Liabilities, Including Any Valuation Allowance	The following table discloses those significant components of our deferred tax assets and liabilities, including any valuation allowance: December 31, 2018 December 31, 2017 Assets Liabilities Assets Liabilities Depreciation and fixed-asset differences $ — $ 297 $ — $ 411 Reserves related to discontinued operations and restructuring charges 24 — 15 — Receivables (doubtful accounts and adjustments) 155 — 134 — Deferred gain on debt exchanges — — — 6 Accruals for retained insurance risks 205 — 225 — Intangible assets — 341 — 330 Other long-term liabilities 39 — 97 — Benefit plans 255 — 268 — Other accrued liabilities 32 — 42 — Investments and other assets — 83 — 79 Interest expense limitation 89 — — — Net operating loss carryforwards 266 — 399 — Stock-based compensation 24 — 27 — Other items 88 32 142 32 1,177 753 1,349 858 Valuation allowance (148 ) — (72 ) — $ 1,029 $ 753 $ 1,277 $ 858
Reconciliation of the Deferred Tax Assets and Liabilities and the Corresponding AmountsReported in the Accompanying Consolidated Balance Sheets	Below is a reconciliation of the deferred tax assets and liabilities and the corresponding amounts reported in the accompanying Consolidated Balance Sheets. December 31, 2018 2017 Deferred income tax assets $ 312 $ 455 Deferred tax liabilities (36 ) (36 ) Net deferred tax asset $ 276 $ 419
Schedule of Changes in Unrecognized Tax Benefits That Have Impacted Deferred Tax Assets and Liabilities	The following table summarizes the total changes in unrecognized tax benefits in continuing operations during the years ended December 31, 2018 , 2017 and 2016 . There were no such changes in discontinued operations. The additions and reductions for tax positions include the impact of items for which the ultimate deductibility is highly certain, but for which there is uncertainty about the timing of such deductions. Such amounts include unrecognized tax benefits that have impacted deferred tax assets and liabilities at December 31, 2018 , 2017 and 2016 . Continuing Operations Balance At December 31, 2015 $ 40 Additions for prior-year tax positions 2 Reductions due to a lapse of statute of limitations (7 ) Balance At December 31, 2016 $ 35 Additions for prior-year tax positions 31 Reductions for tax positions of prior years (15 ) Reductions due to a lapse of statute of limitations (5 ) Balance At December 31, 2017 $ 46 Reductions due to a lapse of statute of limitations (1 ) Balance At December 31, 2018 $ 45

EARNINGS (LOSS) PER COMMON SH_2

EARNINGS (LOSS) PER COMMON SHARE (Tables)	12 Months Ended
	Dec. 31, 2018
Earnings Per Share [Abstract]
Schedule of Reconciliation of Numerators and Denominators of our Basic and Diluted Earnings (Loss) Per Common Share	The following table is a reconciliation of the numerators and denominators of our basic and diluted earnings (loss) per common share calculations for our continuing operations for the years ended December 31, 2018 , 2017 and 2016 . Net earnings available (loss attributable) is expressed in millions and weighted average shares are expressed in thousands. Net Income Available (Loss Attributable) to Common Shareholders (Numerator) Weighted Average Shares (Denominator) Per-Share Amount Year Ended December 31, 2018 Net income available to Tenet Healthcare Corporation common shareholders for basic earnings per share $ 108 102,110 $ 1.06 Effect of dilutive stock options, restricted stock units and deferred compensation units — 1,771 (0.02 ) Net income available to Tenet Healthcare Corporation common shareholders for diluted earnings per share $ 108 103,881 $ 1.04 Year Ended December 31, 2017 Net loss attributable to Tenet Healthcare Corporation common shareholders for basic loss per share $ (704 ) 100,592 $ (7.00 ) Effect of dilutive stock options, restricted stock units and deferred compensation units — — — Net loss attributable to Tenet Healthcare Corporation common shareholders for diluted loss per share $ (704 ) 100,592 $ (7.00 ) Year Ended December 31, 2016 Net loss attributable to Tenet Healthcare Corporation common shareholders for basic losss per share $ (187 ) 99,321 $ (1.88 ) Effect of dilutive stock options, restricted stock units and deferred compensation units — — — Net loss attributable to Tenet Healthcare Corporation common shareholders for diluted earnings per share $ (187 ) 99,321 $ (1.88 )

FAIR VALUE MEASUREMENTS (Tables

FAIR VALUE MEASUREMENTS (Tables)	12 Months Ended
	Dec. 31, 2018
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis	The following tables present this information and indicate the fair value hierarchy of the valuation techniques we utilized to determine such fair values. In general, fair values determined by Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities, which generally are not applicable to non-financial assets and liabilities. Fair values determined by Level 2 inputs utilize data points that are observable, such as definitive sales agreements, appraisals or established market values of comparable assets. Fair values determined by Level 3 inputs are unobservable data points for the asset or liability and include situations where there is little, if any, market activity for the asset or liability, such as internal estimates of future cash flows. . December 31, 2018 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Long-lived assets held for sale $ 39 $ — $ 39 $ — Long-lived assets held and used $ 130 $ — $ 130 $ — December 31, 2017 Quoted Prices in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) Long-lived assets held for sale $ 456 $ — $ 456 $ — Long-lived assets held and used $ — $ — $ — $ — Other than temporarily impaired equity method investments $ 113 $ — $ 113 $ —

ACQUISITIONS (Tables)

ACQUISITIONS (Tables)	12 Months Ended
	Dec. 31, 2018
Business Combinations [Abstract]
Schedule of Preliminary Purchase Price Allocation	Preliminary or final purchase price allocations for all the acquisitions made during the years ended December 31, 2018 , 2017 and 2016 are as follows: 2018 2017 2016 Current assets $ 6 $ 7 $ 51 Property and equipment 19 9 38 Other intangible assets 9 8 7 Goodwill 220 91 464 Other long-term assets, including previously held equity method investments (18 ) (3 ) (56 ) Current liabilities — (8 ) (30 ) Long-term liabilities (15 ) (2 ) (15 ) Redeemable noncontrolling interests in equity of consolidated subsidiaries (21 ) (29 ) (190 ) Noncontrolling interests (85 ) (18 ) (119 ) Cash paid, net of cash acquired (113 ) (50 ) (117 ) Gains on consolidations $ 2 $ 5 $ 33

SEGMENT INFORMATION (Tables)

SEGMENT INFORMATION (Tables)	12 Months Ended
	Dec. 31, 2018
Segment Reporting [Abstract]
Reconciliation of Assets by Reportable Segment to Consolidated Assets	The following table includes amounts for each of our reportable segments and the reconciling items necessary to agree to amounts reported in the accompanying Consolidated Balance Sheets and Consolidated Statements of Operations: December 31, December 31, December 31, Assets: Hospital Operations and other $ 15,684 $ 16,466 $ 17,871 Ambulatory Care 5,711 5,822 5,722 Conifer 1,014 1,097 1,108 Total $ 22,409 $ 23,385 $ 24,701
Reconciliation of Other Significant Reconciling Items From Segments to Consolidated	Years Ended December 31, 2018 2017 2016 Capital expenditures: Hospital Operations and other $ 527 $ 625 $ 799 Ambulatory Care 68 60 51 Conifer 22 22 25 Total $ 617 $ 707 $ 875 Net operating revenues: Hospital Operations and other total prior to inter-segment eliminations $ 15,285 $ 16,260 $ 16,904 Ambulatory Care 2,085 1,940 1,797 Conifer Tenet 590 618 651 Other clients 943 979 920 Total Conifer revenues 1,533 1,597 1,571 Inter-segment eliminations (590 ) (618 ) (651 ) Total $ 18,313 $ 19,179 $ 19,621 Equity in earnings of unconsolidated affiliates: Hospital Operations and other $ 10 $ 4 $ 9 Ambulatory Care 140 140 122 Total $ 150 $ 144 $ 131 Adjusted EBITDA: Hospital Operations and other $ 1,411 $ 1,462 $ 1,586 Ambulatory Care 792 699 615 Conifer 357 283 277 Total $ 2,560 $ 2,444 $ 2,478 Depreciation and amortization: Hospital Operations and other $ 685 $ 736 $ 709 Ambulatory Care 68 84 91 Conifer 49 50 50 Total $ 802 $ 870 $ 850 Adjusted EBITDA $ 2,560 $ 2,444 $ 2,478 Income (loss) from divested and closed businesses 9 (41 ) (37 ) Depreciation and amortization (802 ) (870 ) (850 ) Impairment and restructuring charges, and acquisition-related costs (209 ) (541 ) (202 ) Litigation and investigation costs (38 ) (23 ) (293 ) Interest expense (1,004 ) (1,028 ) (979 ) Gain (loss) from early extinguishment of debt 1 (164 ) — Other non-operating expense, net (5 ) (22 ) (20 ) Net gains on sales, consolidation and deconsolidation of facilities 127 144 151 Income (loss) from continuing operations, before income taxes $ 639 $ (101 ) $ 248

Supplemental Financial Inform_2

Supplemental Financial Information (Tables)	12 Months Ended
	Dec. 31, 2018
Condensed Financial Information Disclosure [Abstract]
Selected Quarterly Financial Information (Unaudited)	SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) Year Ended December 31, 2018 First Second Third Fourth Net operating revenues $ 4,699 $ 4,506 $ 4,489 $ 4,619 Net income $ 191 $ 108 $ 65 $ 102 Net income available (loss attributable) to Tenet Healthcare Corporation common shareholders $ 99 $ 26 $ (9 ) $ (5 ) Earnings (loss) per share available (attributable) to Tenet Healthcare Corporation common shareholders: Basic $ 0.98 $ 0.25 $ (0.09 ) $ (0.04 ) Diluted $ 0.96 $ 0.25 $ (0.09 ) $ (0.04 ) Year Ended December 31, 2017 First Second Third Fourth Net operating revenues $ 4,813 $ 4,802 $ 4,586 $ 4,978 Net income (loss) $ 36 $ 32 $ (289 ) $ (99 ) Net loss attributable to Tenet Healthcare Corporation common shareholders $ (53 ) $ (55 ) $ (367 ) $ (229 ) Loss per share attributable to Tenet Healthcare Corporation common shareholders: Basic $ (0.53 ) $ (0.55 ) $ (3.64 ) $ (2.27 ) Diluted $ (0.53 ) $ (0.55 ) $ (3.64 ) $ (2.27 )

SIGNIFICANT ACCOUNTING POLICI_4

SIGNIFICANT ACCOUNTING POLICIES - Description of Business (Details) $ in Millions	Jul. 03, 2017USD ($)	Apr. 30, 2018USD ($)	Jul. 31, 2017USD ($)	Apr. 30, 2016USD ($)	Dec. 31, 2018hospitalcenter	Mar. 31, 2016
Business Acquisition
Number of hospitals operated by subsidiaries					68
Number of surgical hospitals					23
Number of outpatient centers | center					475
Number of facilities owned by subsidiaries					111
United Surgical Partners International
Business Acquisition
Number of surgical hospitals					23
Payment contributed to joint venture | $	$ 716	$ 630	$ 716	$ 127
Joint venture, ownership percentage	80.00%	15.00%	80.00%	56.30%		50.10%
Redeemable noncontrolling interests | United Surgical Partners International
Business Acquisition
Payment contributed to joint venture | $				$ 127
Joint venture, ownership percentage		95.00%		56.30%
Disposal group, held-for-sale, not discontinued operations
Business Acquisition
Number of hospitals divested					3

SIGNIFICANT ACCOUNTING POLICI_5

SIGNIFICANT ACCOUNTING POLICIES - Basis of Presentation (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018	Jan. 01, 2017
Business Acquisition
Implicit price concessions	$ 4,619	$ 4,489	$ 4,506	$ 4,699	$ 4,978	$ 4,586	$ 4,802	$ 4,813	$ 18,313	$ 19,179	$ 19,621
Deferred income tax assets	$ 312				$ 455				312	455
Salaries, wages and benefits									(8,634)	(9,274)	(9,328)
Accounting Standards Update 2014-09
Business Acquisition
Implicit price concessions									1,422
Contract with customer, asset												$ 171
Accounting Standards Update 2018-02
Business Acquisition
Cumulative effect of accounting change												36
Accounting Standards Update 2016-01
Business Acquisition
Cumulative effect of accounting change												$ 7
Accounting Standards Update 2016-09
Business Acquisition
Cumulative effect of accounting change													$ 56
Deferred income tax assets													$ 56
Adjustments for New Accounting Principle, Early Adoption | Accounting Standards Update 2017-07
Business Acquisition
Salaries, wages and benefits									$ 16	$ 31	$ 28

SIGNIFICANT ACCOUNTING POLICI_6

SIGNIFICANT ACCOUNTING POLICIES SIGNIFICANT ACCOUNTING POLICIES - Net Operating Revenues (Details) (Details)	12 Months Ended
	Dec. 31, 2018
Accounting Policies [Abstract]
Cost report filing period after end of annual cost reporting period	5 years

SIGNIFICANT ACCOUNTING POLICI_7

SIGNIFICANT ACCOUNTING POLICIES - Electronic Health Records Incentives (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Abstract]
Incentive payments for technology certification	$ 3	$ 9	$ 32

SIGNIFICANT ACCOUNTING POLICI_8

SIGNIFICANT ACCOUNTING POLICIES - Cash and Cash Equivalents (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash and Cash Equivalents
Cash and cash equivalents	$ 411	$ 611	$ 716	$ 356
Accrued property and equipment purchases for items received but not yet paid	135	117
Non-cancellable capital leases primarily for buildings and equipment	149	162
Captive insurance subsidiaries
Cash and Cash Equivalents
Cash and cash equivalents	177	179
Health plan related businesses
Cash and Cash Equivalents
Cash and cash equivalents	8	30
Accounts payable
Cash and Cash Equivalents
Book overdrafts classified as accounts payable	288	311
Accrued property and equipment purchases for items received but not yet paid	$ 114	$ 79

SIGNIFICANT ACCOUNTING POLICI_9

SIGNIFICANT ACCOUNTING POLICIES - Investments in Unconsolidated Affiliates (Details) $ in Millions	2 Months Ended	12 Months Ended
	Feb. 28, 2018hospital	Dec. 31, 2018USD ($)hospital	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Schedule of Equity Method Investments [Line Items]
Percentage of investee results reflected on date of acquisition		1
Current assets		$ 842	$ 805	$ 943
Noncurrent assets		662	1,223	991
Current liabilities		(313)	(354)	(320)
Noncurrent liabilities		(430)	(389)	(345)
Noncontrolling interests		(530)	(490)	(494)
Net operating revenues		2,469	2,907	2,823
Net income		599	558	573
Net income attributable to the investees		372	363	343
Equity in earnings of unconsolidated affiliates		150	144	131
Texas Health Ventures Group, LLC
Schedule of Equity Method Investments [Line Items]
Equity in earnings of unconsolidated affiliates		$ 70	$ 69	$ 61
Ambulatory Care
Schedule of Equity Method Investments [Line Items]
Number of outpatient centers recorded not using equity method | hospital		227
Number Of Outpatient Centers Recorded Using Equity Method | hospital		110
Number of outpatient centers | hospital		337
Hospital Operations and other
Schedule of Equity Method Investments [Line Items]
Number of hospitals recorded using equity method | hospital	4
Gain on sale of minority interest in hospitals		$ 11

SIGNIFICANT ACCOUNTING POLIC_10

SIGNIFICANT ACCOUNTING POLICIES - Property and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Buildings and improvements | Minimum
Property and equipment
Useful life	15 years
Buildings and improvements | Maximum
Property and equipment
Useful life	40 years
Equipment | Minimum
Property and equipment
Useful life	3 years
Equipment | Maximum
Property and equipment
Useful life	15 years
Newly constructed hospitals
Property and equipment
Useful life	50 years
Construction in progress
Property and equipment
Interest costs capitalized related to construction projects	$ 7	$ 15	$ 22

SIGNIFICANT ACCOUNTING POLIC_11

SIGNIFICANT ACCOUNTING POLICIES - Goodwill and Other Intangible Assets (Details) - Capitalized software costs	12 Months Ended
	Dec. 31, 2018
Minimum
Goodwill and Other Intangible Assets
Estimated useful life	3 years
Maximum
Goodwill and Other Intangible Assets
Estimated useful life	15 years

SIGNIFICANT ACCOUNTING POLIC_12

SIGNIFICANT ACCOUNTING POLICIES - Insurance and Segments (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Accruals for General and Professional Liability Risks
Risk-free discount rate	2.59%	2.33%

SIGNIFICANT ACCOUNTING POLIC_13

SIGNIFICANT ACCOUNTING POLICIES - Segment Reporting (Details) - hospital	8 Months Ended
	Aug. 16, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition
Revenue generated by general hospitals		80.00%	82.00%	83.00%
United Surgical Partners International | European Surgical Partners Ltd
Business Acquisition
Number of private hospitals	9

EQUITY - Changes in Shareholder

EQUITY - Changes in Shareholders' Equity - Noncontrolling interests (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Noncontrolling Interest [Line Items]
Noncontrolling interests balance	$ 687	$ 539	$ 1,082	$ 958
Net income attributable to noncontrolling interests	276	(559)	(54)
Noncontrolling Interests
Noncontrolling Interest [Line Items]
Noncontrolling interests balance	806	686	665	$ 267
Net income attributable to noncontrolling interests	165	145	138
Noncontrolling Interests | Hospital Operations and other
Noncontrolling Interest [Line Items]
Noncontrolling interests balance	112	64
Net income attributable to noncontrolling interests	8	11	11
Noncontrolling Interests | Ambulatory Care
Noncontrolling Interest [Line Items]
Noncontrolling interests balance	694	622
Net income attributable to noncontrolling interests	$ 157	$ 134	$ 127

ACCOUNTS RECEIVABLE - Component

ACCOUNTS RECEIVABLE - Components (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Accounts receivable and allowance for doubtful accounts
Accounts receivable, net	$ 2,595	$ 2,616
Continuing Operations
Accounts receivable and allowance for doubtful accounts
Patient accounts receivable	2,427	3,376
Allowance for doubtful accounts	0	(898)
Estimated future recoveries	148	132
Net cost reports and settlements payable and valuation allowances	18	4
Accounts receivable, net	2,593	2,614
Discontinued operations
Accounts receivable and allowance for doubtful accounts
Accounts receivable, net	$ 2	$ 2

ACCOUNTS RECEIVABLE - Allowance

ACCOUNTS RECEIVABLE - Allowance (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Accounts receivable and allowance for doubtful accounts
Allowance for doubtful accounts as percent of accounts receivable	26.60%
Estimated costs of caring	$ 764	$ 769	$ 747
Self-pay patients
Accounts receivable and allowance for doubtful accounts
Estimated costs of caring	640	648	609
Charity care patients
Accounts receivable and allowance for doubtful accounts
Estimated costs of caring	124	121	138
Medicaid DSH and other supplemental revenues
Accounts receivable and allowance for doubtful accounts
Estimated costs of caring	$ 847	$ 864	$ 906

ACCOUNTS RECEIVABLE - Other Rec

ACCOUNTS RECEIVABLE - Other Receivables (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Accounts receivable and allowance for doubtful accounts
Receivables	$ 2,595	$ 2,616
Payables	1,207	1,175
California's Provider Fee Program | Other current assets
Accounts receivable and allowance for doubtful accounts
Receivables	278	312
California's Provider Fee Program | Investments and other assets
Accounts receivable and allowance for doubtful accounts
Receivables	231	266
California's Provider Fee Program | Other current liabilities
Accounts receivable and allowance for doubtful accounts
Payables	100	159
California's Provider Fee Program | Other long-term liabilities
Accounts receivable and allowance for doubtful accounts
Payables	$ 42	$ 49

CONTRACT BALANCES - Contract As

CONTRACT BALANCES - Contract Assets for Hospital Operations and Other Segments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Contract with Customer, Asset, Rollforward [Abstract]
Percentage of contract assets that meet the conditions for unconditional right to payment payment	89.00%
Hospital Operations and other:
Contract with Customer, Asset, Rollforward [Abstract]
Receivables	$ 0	$ 0
Increase (decrease) in contract asset	(2)	0
Receivables	$ 169	$ 0

CONTRACT BALANCES - Contract _2

CONTRACT BALANCES - Contract Assets and Liabilities, Conifer (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Change in Contract with Customer, Liability Rollforward [Abstract]
Amount of revenue recognized by Conifer that was included in the opening current deferred revenue liability	$ 72	$ 73
Conifer
Change in Contract with Customer, Asset, Rollforward [Abstract]
Receivables	89	67
Contract asset - unbilled revenue	10	8
Change in receivables	(47)
Change in receivables (cumulative catch up)		22
Change in contract asset - unbilled revenue	1	2
Receivables	42	89
Contract asset - unbilled revenue	11	10
Change in Contract with Customer, Liability Rollforward [Abstract]
Contract liability- current deferred revenue	80	76
Contract liability - long-term deferred revenue	21	26
Contract liability- current deferred revenue	61	80
Contract liability - long-term deferred revenue	20	21
Conifer | Short-term Contract with Customer
Change in Contract with Customer, Liability Rollforward [Abstract]
Change in contract liability	(19)	4
Conifer | Long-term Contract with Customer
Change in Contract with Customer, Liability Rollforward [Abstract]
Change in contract liability	$ (1)	$ (5)

CONTRACT BALANCES - Contract Co

CONTRACT BALANCES - Contract Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue from Contract with Customer [Abstract]
Amortized customer contract costs	$ 11	$ 10	$ 7
Capitalized contract costs	$ 28	$ 35

ASSETS AND LIABILITIES HELD F_3

ASSETS AND LIABILITIES HELD FOR SALE (Details) $ in Millions	3 Months Ended					12 Months Ended
	Sep. 30, 2018USD ($)hospital	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2017hospital	Sep. 30, 2017USD ($)	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Current Assets and Liabilities Held for Sale
Impairment charges						$ 40	$ 364	$ 54
Proceeds from sales of facilities and other assets						543	827	573
Gains on sale of facilities						127	144	151
Disposal group, disposed of by sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Notes issued						17.5
Chicago-area
Current Assets and Liabilities Held for Sale
Number of hospitals | hospital				3
Assets held for sale						107
Liabilities held for sale						(43)
Impairment charges						24	73
California facilities | Disposal group, disposed of by sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Gain (loss) on disposition of business						36
Proceeds from sales of facilities and other assets						53
United Kingdom facilities | Disposal group, held-for-sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Impairment charges						9	59
United Kingdom facilities | Disposal group, disposed of by sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Number of hospitals | hospital	9
Proceeds from sales of facilities and other assets	$ 15
St. Louis, Missouri hospital affiliated operations | Disposal group, disposed of by sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Gain (loss) on disposition of business		$ 12
Proceeds from sales of facilities and other assets		$ 54
MacNeal Hospital
Current Assets and Liabilities Held for Sale
Gain (loss) on disposition of business						90
MacNeal Hospital | Disposal group, disposed of by sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Gain (loss) on disposition of business						90
Proceeds from sales of facilities and other assets						241
Philadelphia facilities
Current Assets and Liabilities Held for Sale
Gain (loss) on disposition of business							232
Philadelphia facilities | Disposal group, held-for-sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Impairment charges							232
Philadelphia facilities | Disposal group, disposed of by sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Gain (loss) on disposition of business						(21)
Proceeds from sales of facilities and other assets						132
Abrazo Maryvale Hospital | Disposal group, disposed of by sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Proceeds from sales of facilities and other assets			$ 7
Houston, Texas facilities
Current Assets and Liabilities Held for Sale
Gain (loss) on disposition of business							111
Houston, Texas facilities | Disposal group, disposed of by sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Gain (loss) on disposition of business						$ (10)
Proceeds from sales of facilities and other assets					$ 750
Gains on sale of facilities							111
Michigan Health Plan Businesses | Disposal group, disposed of by sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Gain (loss) on disposition of business							3
Proceeds from sales of facilities and other assets							20
Arizona Health Plan Businesses | Disposal group, disposed of by sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Gain (loss) on disposition of business							13
Proceeds from sales of facilities and other assets							13
Texas Health Plan Businesses | Disposal group, disposed of by sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Gain (loss) on disposition of business							10
Proceeds from sales of facilities and other assets							$ 12
Georgia Facilities | Disposal group, disposed of by sale, not discontinued operations
Current Assets and Liabilities Held for Sale
Gain (loss) on disposition of business								113
Proceeds from sales of facilities and other assets								$ 575

ASSETS AND LIABILITIES HELD F_4

ASSETS AND LIABILITIES HELD FOR SALE - Net assets held for sale (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current liabilities	$ (43)	$ (480)
Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Accounts receivable	54
Other current assets	13
Investments and other long-term assets	1
Property and equipment	39
Current liabilities	(36)
Long-term liabilities	(7)
Net assets held for sale	$ 64

ASSETS AND LIABILITIES HELD F_5

ASSETS AND LIABILITIES HELD FOR SALE - Significant Components (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment charges	$ 77	$ 402
Disposal group, disposed of by sale, not discontinued operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from continuing operations, before income taxes	48	(163)	$ 5
Disposal group, held-for-sale, not discontinued operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from continuing operations, before income taxes	(41)	(82)	(1)
Houston, Texas facilities
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on disposition of business		111
Houston, Texas facilities | Disposal group, disposed of by sale, not discontinued operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on disposition of business	(10)
Income (loss) from continuing operations, before income taxes	(10)	133	67
Philadelphia facilities
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on disposition of business		232
Philadelphia facilities | Disposal group, disposed of by sale, not discontinued operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on disposition of business	(21)
Income (loss) from continuing operations, before income taxes	(29)	(255)	(75)
MacNeal Hospital
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on disposition of business	90
MacNeal Hospital | Disposal group, disposed of by sale, not discontinued operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain (loss) on disposition of business	90
Income (loss) from continuing operations, before income taxes	93	27	29
Aspen
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment charges	9	59
Aspen | Disposal group, disposed of by sale, not discontinued operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from continuing operations, before income taxes	(6)	(68)	(16)
Chicago-area
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment charges	24	73
Chicago-area | Disposal group, held-for-sale, not discontinued operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income (loss) from continuing operations, before income taxes	$ (41)	$ (82)	$ (1)

IMPAIRMENT AND RESTRUCTURING _2

IMPAIRMENT AND RESTRUCTURING CHARGES, AND ACQUISITION-RELATED COSTS (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)segmenthospital	Dec. 31, 2017USD ($)investment	Dec. 31, 2016USD ($)hospital
Impaired Long-Lived Assets Held and Used [Line Items]
Number of continuing operating segments | segment	3
Net impairment and restructuring charges and acquisition-related costs	$ 209	$ 541	$ 202
Impairment charges	77	402
Restructuring charges	115	117
Acquisition costs	17	22	52
Impairment charges	$ 40	364	$ 54
Number of hospitals with impairment charges | hospital	2		4
Aggregate carrying value of assets held and used of the hospitals for which impairment charges were recorded	$ 130		$ 163
Other impairment charges	4	7	14
Employee severance costs	68	82	35
Lease termination costs	17	15	14
Restructuring costs	30	20	14
Acquisition-related transaction costs	10	6	20
Acquisition integration charges	7	16	32
Investments impairment		$ 31	19
Number of equity method investments with impairment charges | investment		2
Aggregate carrying value of assets held and used for hospital	39	$ 456
Chicago Facilities
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment charges	24	73
Impairment charges	24	73
Aspen
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment charges	9	59
Hospital Operations and other
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment charges	67	337	76
Ambulatory Care
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment charges	9	63	8
Conifer
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment charges	$ 1	$ 2	$ 3

LONG-TERM DEBT AND LEASE OBLI_3

LONG-TERM DEBT AND LEASE OBLIGATIONS - Schedule of Debt (Details) - USD ($) $ in Millions	Dec. 31, 2018	Aug. 31, 2018	May 31, 2018	Mar. 31, 2018	Dec. 31, 2017	Jun. 14, 2017
Debt Instrument [Line Items]
Less current portion	$ 182				$ 146
Long-term debt, net of current portion	$ 14,644				14,791
5.500% due 2019
Debt Instrument [Line Items]
Interest rate, stated percentage	5.50%
6.750% due 2020
Debt Instrument [Line Items]
Interest rate, stated percentage	6.75%
8.125% due 2022
Debt Instrument [Line Items]
Interest rate, stated percentage	8.125%
6.750% due 2023
Debt Instrument [Line Items]
Interest rate, stated percentage	6.75%
7.000% due 2025
Debt Instrument [Line Items]
Interest rate, stated percentage	7.00%
6.875% due 2031
Debt Instrument [Line Items]
Interest rate, stated percentage	6.875%
4.750% due 2020
Debt Instrument [Line Items]
Interest rate, stated percentage	4.75%
6.000% due 2020
Debt Instrument [Line Items]
Interest rate, stated percentage	6.00%
4.500% due 2021
Debt Instrument [Line Items]
Interest rate, stated percentage	4.50%
4.375% due 2021
Debt Instrument [Line Items]
Interest rate, stated percentage	4.375%
4.625% due 2024
Debt Instrument [Line Items]
Interest rate, stated percentage	4.625%
7.500% due 2022
Debt Instrument [Line Items]
Interest rate, stated percentage	7.50%
5.125% due 2025
Debt Instrument [Line Items]
Interest rate, stated percentage	5.125%
Senior Notes
Debt Instrument [Line Items]
Capital leases	$ 425				431
Mortgage notes	75				77
Unamortized issue costs, note discounts and premiums	(184)				(231)
Total long-term debt	14,826				14,937
Less current portion	182				146
Long-term debt, net of current portion	14,644				14,791
Senior Notes | 5.500% due 2019
Debt Instrument [Line Items]
Carrying amount	468				500
Senior Notes | 6.750% due 2020
Debt Instrument [Line Items]
Carrying amount	300				300
Senior Notes | 8.125% due 2022
Debt Instrument [Line Items]
Carrying amount	2,800				2,800
Senior Notes | 6.750% due 2023
Debt Instrument [Line Items]
Carrying amount	1,872				1,900
Interest rate, stated percentage				6.75%
Senior Notes | 7.000% due 2025
Debt Instrument [Line Items]
Carrying amount	478				500
Interest rate, stated percentage				7.00%		7.00%
Senior Notes | 6.875% due 2031
Debt Instrument [Line Items]
Carrying amount	362				430
Interest rate, stated percentage		6.875%	6.875%
Senior Notes | 4.750% due 2020
Debt Instrument [Line Items]
Carrying amount	500				500
Senior Notes | 6.000% due 2020
Debt Instrument [Line Items]
Carrying amount	1,800				1,800
Senior Notes | 4.500% due 2021
Debt Instrument [Line Items]
Carrying amount	850				850
Senior Notes | 4.375% due 2021
Debt Instrument [Line Items]
Carrying amount	1,050				1,050
Senior Notes | 4.625% due 2024
Debt Instrument [Line Items]
Carrying amount	1,870				1,870
Interest rate, stated percentage						4.625%
Senior Notes | 7.500% due 2022
Debt Instrument [Line Items]
Carrying amount	750				750
Senior Notes | 5.125% due 2025
Debt Instrument [Line Items]
Carrying amount	$ 1,410				$ 1,410
Interest rate, stated percentage						5.125%

LONG-TERM DEBT AND LEASE OBLI_4

LONG-TERM DEBT AND LEASE OBLIGATIONS - Credit Agreement and Letter of Credit Facility (Details)	12 Months Ended
	Dec. 31, 2018USD ($)
Credit Agreement
Debt Instrument [Line Items]
Revolving credit facility, maximum borrowing capacity	$ 1,000,000,000
Line of credit facility, subfacility maximum available capacity	300,000,000
Standby letters of credit outstanding	2,000,000
Amount available for borrowing under revolving credit facility	$ 998,000,000
Credit Agreement | Minimum
Debt Instrument [Line Items]
Unused commitment fee	0.25%
Credit Agreement | Maximum
Debt Instrument [Line Items]
Unused commitment fee	0.375%
Credit Agreement | Base rate | Minimum
Debt Instrument [Line Items]
Percentage margin on variable rate	0.25%
Credit Agreement | Base rate | Maximum
Debt Instrument [Line Items]
Percentage margin on variable rate	0.75%
Credit Agreement | LIBOR | Minimum
Debt Instrument [Line Items]
Percentage margin on variable rate	1.25%
Credit Agreement | LIBOR | Maximum
Debt Instrument [Line Items]
Percentage margin on variable rate	1.75%
Letter of Credit Facility
Debt Instrument [Line Items]
Revolving credit facility, maximum borrowing capacity	$ 180,000,000
Standby letters of credit outstanding	93,000,000
Borrowing capacity after increase subject to certain conditions	$ 200,000,000
Unused commitment fee percentage after step down	0.50%
Secured debt to EBITDA ratio	3
Issuance fee percentage	1.50%
Issuance fee percentage, based on face amount	0.125%
Letter of Credit Facility | Maximum
Debt Instrument [Line Items]
Number of business days after notice for reimbursement of drawings	3 years

LONG-TERM DEBT AND LEASE OBLI_5

LONG-TERM DEBT AND LEASE OBLIGATIONS - Senior Secured Notes and Senior Unsecured Notes (Details) - USD ($)

1 Months Ended

3 Months Ended

12 Months Ended

Dec. 31, 2018

Nov. 30, 2018

Aug. 31, 2018

May 31, 2018

Mar. 31, 2018

Jun. 30, 2018

Mar. 31, 2018

Sep. 30, 2017

Jun. 30, 2017

Dec. 31, 2018

Dec. 31, 2017

Dec. 31, 2016

Sep. 11, 2017

Aug. 01, 2017

Jul. 14, 2017

Jun. 14, 2017

Debt Instrument [Line Items]

Loss (gain) from early extinguishment of debt

$ (1,000,000)

$ 164,000,000

$ 0

5.500% due 2019

Debt Instrument [Line Items]

Interest rate, stated percentage

5.50%

5.50%

6.875% due 2031

Debt Instrument [Line Items]

Interest rate, stated percentage

6.875%

6.875%

6.750% due 2023

Debt Instrument [Line Items]

Interest rate, stated percentage

6.75%

6.75%

7.000% due 2025

Debt Instrument [Line Items]

Interest rate, stated percentage

7.00%

7.00%

4.625% due 2024

Debt Instrument [Line Items]

Interest rate, stated percentage

4.625%

4.625%

5.125% due 2025

Debt Instrument [Line Items]

Interest rate, stated percentage

5.125%

5.125%

Senior Notes

Debt Instrument [Line Items]

Loss (gain) from early extinguishment of debt

$ 26,000,000

Redemption price percentage

100.00%

Repurchase obligation due to change of control percentage of principal

101.00%

Senior Notes | 5.500% due 2019

Debt Instrument [Line Items]

Repurchased face amount

$ 22,000,000

$ 10,000,000

$ 22,000,000

Proceeds from (repayments of) notes payable

$ 10,000,000

$ 22,000,000

Senior Notes | 6.875% due 2031

Debt Instrument [Line Items]

Repurchased face amount

$ 38,000,000

$ 30,000,000

Interest rate, stated percentage

6.875%

6.875%

Proceeds from (repayments of) notes payable

$ 36,000,000

$ 28,000,000

Amount of accrued and unpaid interest included in purchase price

$ 1,000,000

Loss (gain) from early extinguishment of debt

$ 1,000,000

Senior Notes | 6.750% due 2023

Debt Instrument [Line Items]

Repurchased face amount

$ 28,000,000

$ 28,000,000

Interest rate, stated percentage

6.75%

6.75%

Senior Notes | 7.000% due 2025

Debt Instrument [Line Items]

Repurchased face amount

$ 22,000,000

$ 22,000,000

Interest rate, stated percentage

7.00%

7.00%

7.00%

Proceeds from (repayments of) notes payable

$ 51,000,000

Amount of accrued and unpaid interest included in purchase price

$ 1,000,000

Loss (gain) from early extinguishment of debt

$ 1,000,000

Aggregate principal amount

$ 500,000,000

Senior Notes | 4.625% due 2024

Debt Instrument [Line Items]

Interest rate, stated percentage

4.625%

Aggregate principal amount

$ 830,000,000

Senior Notes | Floating % due 2020

Debt Instrument [Line Items]

Repurchased face amount

$ 900,000,000

Loss (gain) from early extinguishment of debt

$ 138,000,000

Senior Notes | Senior Secured First Lien Notes

Debt Instrument [Line Items]

Interest rate, stated percentage

4.625%

Aggregate principal amount

$ 1,040,000,000

Senior Notes | 5.125% due 2025

Debt Instrument [Line Items]

Interest rate, stated percentage

5.125%

Aggregate principal amount

$ 1,410,000,000

Senior Notes | 6.250% due 2018

Debt Instrument [Line Items]

Repurchased face amount

$ 1,041,000,000

Interest rate, stated percentage

6.25%

Senior Notes | 5.000% due 2019

Debt Instrument [Line Items]

Repurchased face amount

$ 1,100,000,000

Interest rate, stated percentage

5.00%

Senior Notes | 8.000% due 2020

Debt Instrument [Line Items]

Repurchased face amount

$ 250,000,000

$ 500,000,000

Interest rate, stated percentage

8.00%

8.00%

LONG-TERM DEBT AND LEASE OBLI_6

LONG-TERM DEBT AND LEASE OBLIGATIONS - Covenants (Details)	12 Months Ended
	Dec. 31, 2018USD ($)
Credit Agreement
Covenants
Threshold limit of revolving credit facility	$ 100,000,000
Threshold limit of unused borrowing availability under the revolving credit facility (less than)	$ 100,000,000
Threshold limit of unused borrowing availability under the revolving credit facility, number of consecutive days	3 years
Senior Notes | Maximum
Covenants
Secured debt ratio	4
Asset value as a percentage of consolidated net tangible assets for properties to be defined as principal property	15.00%
Senior Notes | Minimum
Covenants
Secured debt ratio	3
Asset value as a percentage of consolidated net tangible assets for properties to be defined as principal property	5.00%

LONG-TERM DEBT AND LEASE OBLI_7

LONG-TERM DEBT AND LEASE OBLIGATIONS - Debt Maturities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Long-term debt, including capital lease obligations
Total	$ 15,010
2,019	182
2,020	2,697
2,021	1,958
2,022	3,588
2,023	1,894
Later Years	4,691
Long-term non-cancelable operating leases
Total	932
2,019	171
2,020	151
2,021	133
2,022	113
2,023	92
Later Years	272
Rental expense
Rental expense under operating leases	326	$ 340	$ 335
Sublease income	$ 11	$ 14	$ 13

GUARANTEES (Details)

GUARANTEES (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)
Income guarantee
GUARANTEES
Guarantee obligation period	12 months
Commitment period	3 years
Revenue collection guarantees | Minimum
GUARANTEES
Guarantee obligation period	1 year
Revenue collection guarantees | Maximum
GUARANTEES
Guarantee obligation period	3 years
Income and revenue collection guarantee
GUARANTEES
Maximum potential amount of future payments under guarantees	$ 166
Income and revenue collection guarantee | Other current liabilities
GUARANTEES
Liability for the fair value of guarantees	123
Guaranteed investees of third parties
GUARANTEES
Liability for the fair value of guarantees	24
Guarantee obligations for consolidated subsidiaries	$ 8

EMPLOYEE BENEFIT PLANS (Details

EMPLOYEE BENEFIT PLANS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
EMPLOYEE BENEFIT PLANS
Stock-based compensation costs, pretax	$ 46	$ 59	$ 60
Restricted Stock Units
EMPLOYEE BENEFIT PLANS
Stock-based compensation costs, pretax	$ 46
Portion of awards vesting on each of the first three anniversary dates of the grant	33.33%
2008 Stock Incentive Plan
EMPLOYEE BENEFIT PLANS
Shares available for issuance under the plan (in shares)	5,300,000
Shares available assuming maximum performance (in shares)	4,100,000
Vesting period	3 years
2008 Stock Incentive Plan | Stock Options
EMPLOYEE BENEFIT PLANS
Expiration period from the date of grant	10 years
2008 Stock Incentive Plan | Restricted Stock Units
EMPLOYEE BENEFIT PLANS
Contractual right to receive shares of common stock for a stock based award (in shares)	1
Portion of awards vesting on each of the first three anniversary dates of the grant	33.33%
Vesting period	3 years

EMPLOYEE BENEFIT PLANS - Grant

EMPLOYEE BENEFIT PLANS - Grant Dates Options and RSUs (Details) - USD ($) $ / shares in Units, $ in Millions	Mar. 01, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	May 31, 2018	Feb. 28, 2018	Sep. 29, 2017
EMPLOYEE BENEFIT PLANS
Fair Value Per Share at Grant Date (in dollars per share)		$ 9.16	$ 7.64
Stock-based compensation costs, pretax		$ 46	$ 59	$ 60
Stock Options
EMPLOYEE BENEFIT PLANS
Awards (in shares)		635,196	1,396,307	0
Stock Options | February 28, 2018
EMPLOYEE BENEFIT PLANS
Awards (in shares)		593,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 8.83
Stock-based compensation costs, pretax		$ 2
Stock Options | September 29, 2017
EMPLOYEE BENEFIT PLANS
Awards (in shares)		409,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 5.63
Stock-based compensation costs, pretax		$ 2
Stock Options | March 1, 2017
EMPLOYEE BENEFIT PLANS
Awards (in shares)		877,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 8.52
Stock-based compensation costs, pretax		$ 1
Restricted Stock Units
EMPLOYEE BENEFIT PLANS
Stock-based compensation costs, pretax		$ 46
Restricted Stock Units | February 28, 2018
EMPLOYEE BENEFIT PLANS
Awards (in shares)		272,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 20.60
Stock-based compensation costs, pretax		$ 2
Restricted Stock Units | March 1, 2017
EMPLOYEE BENEFIT PLANS
Awards (in shares)		404,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 18.99
Stock-based compensation costs, pretax		$ 2
Restricted Stock Units | June 28, 2018
EMPLOYEE BENEFIT PLANS
Awards (in shares)		51,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 34.61
Stock-based compensation costs, pretax		$ 1
Restricted Stock Units | May 4, 2018
EMPLOYEE BENEFIT PLANS
Awards (in shares)		54,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 23.53
Stock-based compensation costs, pretax		$ 1
Restricted Stock Units | March 29, 2018
EMPLOYEE BENEFIT PLANS
Awards (in shares)		293,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 24.25
Stock-based compensation costs, pretax		$ 3
Restricted Stock Units | June 30, 2016
EMPLOYEE BENEFIT PLANS
Awards (in shares)		113,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 27.64
Stock-based compensation costs, pretax		$ 1
Restricted Stock Units | May 31, 2016
EMPLOYEE BENEFIT PLANS
Awards (in shares)		54,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 28.94
Stock-based compensation costs, pretax		$ 1
Restricted Stock Units | March 10, 2016
EMPLOYEE BENEFIT PLANS
Awards (in shares)		566,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 25.50
Stock-based compensation costs, pretax		$ 3
Restricted Stock Units | February 25, 2015
EMPLOYEE BENEFIT PLANS
Awards (in shares)		1,374,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 45.63
Stock-based compensation costs, pretax		$ 1
Restricted Stock Units | August 25, 2014
EMPLOYEE BENEFIT PLANS
Awards (in shares)		460,000
Fair Value Per Share at Grant Date (in dollars per share)		$ 59.90
Stock-based compensation costs, pretax		$ 4
Restricted Stock Units | Other grants
EMPLOYEE BENEFIT PLANS
Stock-based compensation costs, pretax		4
Equity Option | USPI Management Equity Plan
EMPLOYEE BENEFIT PLANS
Stock-based compensation costs, pretax		$ 18
Board of Directors Chairman | Stock Options | February 28, 2018
EMPLOYEE BENEFIT PLANS
Exercise price (in dollars per share)							$ 20.60
Board of Directors Chairman | Stock Options | September 29, 2017
EMPLOYEE BENEFIT PLANS
Exercise price (in dollars per share)								$ 16.43
Officer | Stock Options
EMPLOYEE BENEFIT PLANS
Awards (in shares)	987,781
Exercise price (in dollars per share)					$ 20.60	$ 35.43		$ 16.43
Officer | Stock Options | March 1, 2017
EMPLOYEE BENEFIT PLANS
Exercise price (in dollars per share)	$ 18.99

EMPLOYEE BENEFIT PLANS - Stock

EMPLOYEE BENEFIT PLANS - Stock Options (Details) - USD ($) $ / shares in Units, $ in Millions	May 31, 2018	Feb. 28, 2018	Sep. 29, 2017	Mar. 01, 2017	Jun. 30, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Weighted Average Remaining Life
Fair value per share at grant date (in dollars per share)						$ 9.16	$ 7.64
Fair Value, Option, Assumptions Used [Abstract]
Expected volatility		46.00%	46.00%	49.00%
Expected dividend yield		0.00%	0.00%	0.00%
Expected life		6 years 2 months 12 days	3 years	6 years 2 months 12 days
Expected forfeiture rate		0.00%	0.00%	0.00%
Risk-free interest rate		2.72%	1.92%	2.15%
Stock Options
Stock option activity
Outstanding at the beginning of the period (in shares)						2,564,822	1,435,921	1,606,842
Granted (in shares)						635,196	1,396,307	0
Exercised (in shares)						(619,849)	(20,400)	(111,715)
Forfeited/Expired (in shares)						(317,426)	(247,006)	(59,206)
Outstanding at the end of the period (in shares)						2,262,743	2,564,822	1,435,921
Vested and expected to vest at the end of the period (in shares)						2,262,743
Exercisable at the end of the period (in shares)						767,037
Weighted Average Exercise Price Per Share
Outstanding at the beginning of the period (in dollars per share)						$ 20.35	$ 22.87	$ 22.87
Granted (in dollars per share)						21.33	18.24	0
Exercised (in dollars per share)						18.19	4.56	17.88
Forfeited/Expired (in dollars per share)						35.30	24.37	18.68
Outstanding at the end of the period (in dollars per share)						19.12	$ 20.35	$ 22.87
Vested and expected to vest at the end of the period (in dollars per share)						19.12
Exercisable at the end of the period (in dollars per share)						$ 17.47
Aggregate Intrinsic Value
Outstanding at the end of the period						$ 1
Vested and expected to vest at the end of the period						1
Exercisable at the end of the period						$ 1
Weighted Average Remaining Life
Outstanding at the end of the period						6 years 8 months 12 days
Vested and expected to vest at the end of the period						6 years 8 months 12 days
Exercisable at the end of the period						3 years 2 months 12 days
Aggregate intrinsic value of awards exercised						$ 4	$ 1
Stock Options | Executive Chairman
Weighted Average Remaining Life
Percentage of stock price premium					25.00%
Stock Options | Senior Officers
Stock option activity
Granted (in shares)				987,781
Weighted Average Remaining Life
Targeted share price (in dollars per share)	$ 44.29	$ 25.75		$ 23.74
Percentage of stock price premium	25.00%			25.00%	25.00%
Share price (in dollars per share)	$ 35.43		$ 16.43		$ 20.60
Number of consecutive trading days					20 days
Vesting date subject to conditions	3 years				3 years
Performance Based Stock Options
Stock option activity
Granted (in shares)						635,196	1,396,307
Performance Based Stock Options | Executive Chairman
Stock option activity
Granted (in shares)	31,184	604,012	408,526
Weighted Average Remaining Life
Targeted share price (in dollars per share)					$ 20.53
Number of consecutive trading days					30 days
Vesting date subject to conditions					4 years
Grant Date March12017 | Stock Options
Stock option activity
Granted (in shares)						877,000
Weighted Average Remaining Life
Fair value per share at grant date (in dollars per share)						$ 8.52
Grant Date March12017 | Stock Options | Senior Officers
Weighted Average Remaining Life
Share price (in dollars per share)				$ 18.99

EMPLOYEE BENEFIT PLANS - Range

EMPLOYEE BENEFIT PLANS - Range of Exercise Prices (Details) - Stock Options	12 Months Ended
	Dec. 31, 2018$ / sharesshares
Options Outstanding
Number of options outstanding (in shares) | shares	2,262,743
Weighted Average Remaining Contractual Life	6 years 8 months 12 days
Weighted average exercise price (in dollars per share)	$ 19.12
Options Exercisable
Number of options exercisable (in shares) | shares	767,037
Weighted average exercise price (in dollars per share)	$ 17.47
$0.00 to $4.569
Summary information about outstanding stock options
Upper range of stock exercise price range (in dollars per share)	4.569
Lower range of stock exercise price range (in dollars per share)	$ 0
Options Outstanding
Number of options outstanding (in shares) | shares	82,409
Weighted Average Remaining Contractual Life	2 months 12 days
Weighted average exercise price (in dollars per share)	$ 4.56
Options Exercisable
Number of options exercisable (in shares) | shares	82,409
Weighted average exercise price (in dollars per share)	$ 4.56
$4.57 to $19.759
Summary information about outstanding stock options
Upper range of stock exercise price range (in dollars per share)	19.759
Lower range of stock exercise price range (in dollars per share)	$ 4.57
Options Outstanding
Number of options outstanding (in shares) | shares	1,285,795
Weighted Average Remaining Contractual Life	6 years 8 months 12 days
Weighted average exercise price (in dollars per share)	$ 18.18
Options Exercisable
Number of options exercisable (in shares) | shares	413,960
Weighted average exercise price (in dollars per share)	$ 16.46
$19.76 to $35.430
Summary information about outstanding stock options
Upper range of stock exercise price range (in dollars per share)	35.430
Lower range of stock exercise price range (in dollars per share)	$ 19.76
Options Outstanding
Number of options outstanding (in shares) | shares	894,539
Weighted Average Remaining Contractual Life	7 years 4 months 24 days
Weighted average exercise price (in dollars per share)	$ 21.83
Options Exercisable
Number of options exercisable (in shares) | shares	270,668
Weighted average exercise price (in dollars per share)	$ 22.94

EMPLOYEE BENEFIT PLANS - Employ

EMPLOYEE BENEFIT PLANS - Employee Options (Details) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
EMPLOYEE BENEFIT PLANS
% of Total	100.00%
% of all outstanding options	100.00%
Current employees
EMPLOYEE BENEFIT PLANS
Options outstanding (in shares)	1,616,954
% of Total	71.50%
Former employees
EMPLOYEE BENEFIT PLANS
Options outstanding (in shares)	645,789
% of Total	28.50%
Stock Options
EMPLOYEE BENEFIT PLANS
Options outstanding (in shares)	2,262,743	2,564,822	1,435,921	1,606,842
Market price of the entity's common stock (in dollars per share)	$ 17.14
Stock Options | Current employees
EMPLOYEE BENEFIT PLANS
% of Total	71.50%
Stock Options | Former employees
EMPLOYEE BENEFIT PLANS
% of Total	28.50%
In-the-Money Options
EMPLOYEE BENEFIT PLANS
Options outstanding (in shares)	490,935
% of Total	100.00%
% of all outstanding options	21.70%
In-the-Money Options | Current employees
EMPLOYEE BENEFIT PLANS
Options outstanding (in shares)	469,849
% of Total	95.70%
In-the-Money Options | Former employees
EMPLOYEE BENEFIT PLANS
Options outstanding (in shares)	21,086
% of Total	4.30%
Out-of-the-Money Options
EMPLOYEE BENEFIT PLANS
Options outstanding (in shares)	1,771,808
% of Total	100.00%
% of all outstanding options	78.30%
Out-of-the-Money Options | Current employees
EMPLOYEE BENEFIT PLANS
Options outstanding (in shares)	1,147,105
% of Total	64.70%
Out-of-the-Money Options | Former employees
EMPLOYEE BENEFIT PLANS
Options outstanding (in shares)	624,703
% of Total	35.30%

EMPLOYEE BENEFIT PLANS - Restri

EMPLOYEE BENEFIT PLANS - Restricted Stock Units (Details) $ / shares in Units, $ in Millions	1 Months Ended				2 Months Ended	12 Months Ended
	Oct. 31, 2018member	May 31, 2018membershares	Nov. 30, 2017member	May 31, 2017shares	Nov. 30, 2017member	Dec. 31, 2018USD ($)$ / sharesshares	Dec. 31, 2017$ / sharesshares	Dec. 31, 2016$ / sharesshares
Other Disclosures
New directors | member	1	2	2		3
Restricted Stock Units
Restricted Stock Units
Unvested at the beginning of the period (in shares)						2,253,988	3,174,533	3,627,232
Granted (in shares)						765,184	714,018	1,626,329
Vested (in shares)						(995,331)	(1,397,953)	(1,644,616)
Forfeited (in shares)						(139,711)	(236,610)	(434,412)
Unvested at the end of the period (in shares)						1,884,130	2,253,988	3,174,533
Weighted Average Grant Date Fair Value Per Unit
Unvested at the beginning of the period (in dollars per share) | $ / shares						$ 35.20	$ 38.75	$ 44.69
Granted (in dollars per share) | $ / shares						24.74	18.25	30.05
Vested (in dollars per share) | $ / shares						32.63	35.50	42.95
Forfeited (in dollars per share) | $ / shares						36.01	32.13	38.59
Unvested at the end of the period (in dollars per share) | $ / shares						$ 32.25	$ 35.20	$ 38.75
Other Disclosures
Awards vesting						33.33%
Unrecognized compensation costs | $						$ 18
Period for recognition of unrecognized compensation costs						1 year 5 months 24 days
Restricted Stock Units | Time-vesting
Restricted Stock Units
Granted (in shares)						765,184	714,018
Other Disclosures
Restricted stock that will vest and be settled over a two-year period from the grant date (in shares)						339,806
Vesting period							3 years
Restricted stock that will vest and be settled on the third anniversary of the grant date (in shares)						60,963
Restricted Stock Units | Time-vesting | Non Employee Directors
Other Disclosures
Restricted stock that will vest and be settled on the third anniversary of the grant date (in shares)		54,198		145,179
Restricted Stock Units | Time-vesting | Director
Restricted Stock Units
Granted (in shares)						3,670	13,772
Other Disclosures
Pro-rated annual grant (in shares)						12,154	23,935
Restricted Stock Units | Three-year period from grant date
Other Disclosures
Restricted stock that will vest and be settled over a two-year period from the grant date (in shares)						288,325	518,229
Restricted Stock Units | Time Based Vesting, Two Years
Other Disclosures
Vesting period						2 years
Restricted Stock Units | Time Based Vesting, Three Years
Other Disclosures
Vesting period						3 years
Restricted Stock Units | Performance-based vesting | Minimum
Other Disclosures
Awards vesting							0.00%
Restricted Stock Units | Performance-based vesting | Maximum
Other Disclosures
Awards vesting							200.00%
Restricted Stock Units | Performance-based vesting | Senior Officers
Restricted Stock Units
Granted (in shares)						6,068	12,903
Other Disclosures
Vesting period							3 years

EMPLOYEE BENEFIT PLANS EMPLOYEE

EMPLOYEE BENEFIT PLANS EMPLOYEE BENEFIT PLANS - USPI Management Equity Plan (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Stock-based compensation costs, pretax	$ 46	$ 59	$ 60
USPI Management Equity Plan | Equity Option
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Stock-based compensation costs, pretax	$ 18
USPI Management Equity Plan | Nonqualified Plan | Equity Option
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Portion of awards vesting on each of the first three anniversary dates of the grant	50.00%
Requisite holding period for shares issued under the plan	6 months 1 day
Stock-based compensation costs, pretax	$ 18	$ 13	$ 10
Minimum | USPI Management Equity Plan | Nonqualified Plan | Equity Option
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Percent of common stock allocated to plan	10.00%
Expiration period from the date of grant	7 years
Vesting period	3 years
Maximum | USPI Management Equity Plan | Nonqualified Plan | Equity Option
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Vesting period	4 years

EMPLOYEE BENEFIT PLANS - Empl_2

EMPLOYEE BENEFIT PLANS - Employee Stock Purchase Plan (Details) - Employee Stock Purchase Plan - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
EMPLOYEE BENEFIT PLANS
Number of shares authorized to be issued under the plan (in shares)	5,062,500
Shares available for issuance under the plan (in shares)	3,200,000
Percentage of closing price at which shares are purchased by participant	95.00%
Requisite holding period for shares issued under the plan	1 year
Fair market value per employee per year	$ 25,000
Number of shares (in shares)	228,045	395,957	217,184
Weighted average price (in dollars per share)	$ 22.96	$ 17.28	$ 17.21
Minimum
EMPLOYEE BENEFIT PLANS
Base earnings elected to be withheld each quarter by eligible employees to purchase shares of the entity's common stock	1.00%
Maximum
EMPLOYEE BENEFIT PLANS
Base earnings elected to be withheld each quarter by eligible employees to purchase shares of the entity's common stock	10.00%

EMPLOYEE BENEFIT PLANS - Empl_3

EMPLOYEE BENEFIT PLANS - Employee Retirement Plans (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)plan	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)
Employee Retirement Plans
Contribution expense	$ 99	$ 128	$ 116
Projected benefit obligations
Beginning obligations	(1,455)	(1,475)
Service cost	(2)	(2)	(2)
Interest cost	(56)	(62)	(69)
Actuarial gain (loss)	90	(31)
Benefits paid	122	120
Special termination benefit costs	0	(5)
Ending obligations	(1,301)	(1,455)	(1,475)
Fair value of plans assets
Beginning plan assets	850	786
Gain (loss) on plan assets	(65)	122
Employer contribution	47	43
Benefits paid	(101)	(101)
Ending plan assets	731	850	786
Funded status of plans	(570)	(605)
Amounts recognized in the Consolidated Balance Sheets consist of:
Other current liability	(49)	(69)
Other long-term liability	(521)	(536)
Accumulated other comprehensive loss	281	266
Accumulated Benefit Obligations Assumptions
Accumulated benefit obligation	1,299	1,448
Components of net periodic benefit costs
Service costs	2	2	2
Interest costs	56	62	69
Expected return on plan assets	(54)	(50)	(51)
Amortization of net actuarial loss	14	14	12
Net periodic benefit cost	18	28	32
Net Periodic Benefit Costs Assumptions:
Gain (loss) adjustments recorded in other comprehensive income (loss)	(15)	56	(61)
Net actuarial gains/(losses)	(29)	42	(73)
Cumulative net actuarial losses	281	266	322
Maximum
Net Periodic Benefit Costs Assumptions:
Unrecognized prior service costs	$ 1	$ 1	$ 1
SERP
Employee Retirement Plans
Number of ended SERPs | plan	1
Number of frozen plans | plan	3
Accumulated Benefit Obligations Assumptions
Discount rate	4.50%	3.75%
Compensation increase rate	3.00%	3.00%
Net Periodic Benefit Costs Assumptions:
Discount rate	3.75%	4.25%	4.75%
Compensation increase rate	3.00%	3.00%	3.00%
Pension Plan
Employee Retirement Plans
Decrease in projected benefit obligations	$ 4	$ 10
Fair value of plans assets
Beginning plan assets	850
Ending plan assets	$ 731	$ 850
Accumulated Benefit Obligations Assumptions
Discount rate	4.62%	4.00%
Net Periodic Benefit Costs Assumptions:
Discount rate	4.00%	4.42%	4.67%
Long-term rate of return on assets	6.50%	6.50%	6.50%

EMPLOYEE BENEFIT PLANS - Asset

EMPLOYEE BENEFIT PLANS - Asset Allocations (Details) - Pension Plan	12 Months Ended
	Dec. 31, 2018
Weighted-average asset allocations by asset category
Allowable deviation percentage from target	10.00%
Cash and cash equivalents
Weighted-average asset allocations by asset category
Target	2.00%
Actual	2.00%
U.S. government obligations
Weighted-average asset allocations by asset category
Target	0.00%
Actual	2.00%
Equity securities
Weighted-average asset allocations by asset category
Target	64.00%
Actual	65.00%
Debt securities
Weighted-average asset allocations by asset category
Target	34.00%
Actual	31.00%
Alternative investments
Weighted-average asset allocations by asset category
Target	1.00%
Actual	1.00%

EMPLOYEE BENEFIT PLANS - SERP a

EMPLOYEE BENEFIT PLANS - SERP and DMC (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Employee Retirement Plans
Fair value of DMC Pension Plan assets	$ 731	$ 850	$ 786
SERP and DMC Pension Plan
Total	897
2,019	86
2,020	89
2,021	90
2,022	91
2,023	91
Five Years Thereafter	450
Amounts recognized in the Consolidated Balance Sheets consist of:
Benefit plan obligations	(570)	(605)
Other current liability	49	69
Defined benefit plan obligations	521	536
Expected contribution to the plan for 2019	49
Pension Plan
Employee Retirement Plans
Fair value of DMC Pension Plan assets	731	850
Pension Plan | Cash and cash equivalents
Employee Retirement Plans
Fair value of DMC Pension Plan assets	33	49
Pension Plan | U.S. government obligations
Employee Retirement Plans
Fair value of DMC Pension Plan assets	9	5
Pension Plan | Equity securities
Employee Retirement Plans
Fair value of DMC Pension Plan assets	423	488
Pension Plan | Fixed income funds
Employee Retirement Plans
Fair value of DMC Pension Plan assets	262	308
Pension Plan | Alternative investments
Employee Retirement Plans
Fair value of DMC Pension Plan assets	4
Pension Plan | Level 1
Employee Retirement Plans
Fair value of DMC Pension Plan assets	731	850
Pension Plan | Level 1 | Cash and cash equivalents
Employee Retirement Plans
Fair value of DMC Pension Plan assets	33	49
Pension Plan | Level 1 | U.S. government obligations
Employee Retirement Plans
Fair value of DMC Pension Plan assets	9	5
Pension Plan | Level 1 | Equity securities
Employee Retirement Plans
Fair value of DMC Pension Plan assets	423	488
Pension Plan | Level 1 | Fixed income funds
Employee Retirement Plans
Fair value of DMC Pension Plan assets	262	308
Pension Plan | Level 1 | Alternative investments
Employee Retirement Plans
Fair value of DMC Pension Plan assets	4
Pension Plan | Level 2
Employee Retirement Plans
Fair value of DMC Pension Plan assets	0	0
Pension Plan | Level 2 | Cash and cash equivalents
Employee Retirement Plans
Fair value of DMC Pension Plan assets	0	0
Pension Plan | Level 2 | U.S. government obligations
Employee Retirement Plans
Fair value of DMC Pension Plan assets	0	0
Pension Plan | Level 2 | Equity securities
Employee Retirement Plans
Fair value of DMC Pension Plan assets	0	0
Pension Plan | Level 2 | Fixed income funds
Employee Retirement Plans
Fair value of DMC Pension Plan assets	0	0
Pension Plan | Level 2 | Alternative investments
Employee Retirement Plans
Fair value of DMC Pension Plan assets	0
Pension Plan | Level 3
Employee Retirement Plans
Fair value of DMC Pension Plan assets	0	0
Pension Plan | Level 3 | Cash and cash equivalents
Employee Retirement Plans
Fair value of DMC Pension Plan assets	0	0
Pension Plan | Level 3 | U.S. government obligations
Employee Retirement Plans
Fair value of DMC Pension Plan assets	0	0
Pension Plan | Level 3 | Equity securities
Employee Retirement Plans
Fair value of DMC Pension Plan assets	0	0
Pension Plan | Level 3 | Fixed income funds
Employee Retirement Plans
Fair value of DMC Pension Plan assets	0	$ 0
Pension Plan | Level 3 | Alternative investments
Employee Retirement Plans
Fair value of DMC Pension Plan assets	$ 0

PROPERTY AND EQUIPMENT - Compon

PROPERTY AND EQUIPMENT - Components (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Components of property and equipment
Gross property and equipment	$ 12,214	$ 11,769
Accumulated depreciation and amortization	(5,221)	(4,739)
Net property and equipment	6,993	7,030
Land
Components of property and equipment
Gross property and equipment	613	602
Buildings and improvements
Components of property and equipment
Gross property and equipment	6,920	6,837
Construction in progress
Components of property and equipment
Gross property and equipment	199	109
Equipment
Components of property and equipment
Gross property and equipment	$ 4,482	$ 4,221

GOODWILL AND OTHER INTANGIBLE_3

GOODWILL AND OTHER INTANGIBLE ASSETS - Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Changes in the carrying amount of goodwill
Total	$ 7,018
Total	7,281	$ 7,018
Hospital Operations and other
Changes in the carrying amount of goodwill
Goodwill	5,410	5,406	$ 5,803
Accumulated impairment losses	(2,430)	(2,430)	(2,430)
Total	2,976	3,373
Goodwill acquired during the year and purchase price allocation adjustments	1	5
Goodwill related to assets held for sale and disposed or deconsolidated facilities	3	(402)
Total	2,980	2,976
Ambulatory Care
Changes in the carrying amount of goodwill
Goodwill	3,696	3,437	3,447
Accumulated impairment losses	0	0	0
Total	3,437	3,447
Goodwill acquired during the year and purchase price allocation adjustments	219	86
Goodwill related to assets held for sale and disposed or deconsolidated facilities	40	(103)
Impact of foreign currency translation	0	7
Total	3,696	3,437
Conifer
Changes in the carrying amount of goodwill
Goodwill	605	605	605
Accumulated impairment losses	0	0	$ 0
Total	605	605
Goodwill acquired during the year and purchase price allocation adjustments	0	0
Total	$ 605	$ 605

GOODWILL AND OTHER INTANGIBLE_4

GOODWILL AND OTHER INTANGIBLE ASSETS - Other Intangible Assets (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Information regarding other intangible assets
Gross Carrying Amount	$ 2,744	$ 2,649
Accumulated Amortization	(1,013)	(883)
Net Book Value	1,731	1,766
Capitalized software costs
Information regarding other intangible assets
Gross Carrying Amount	1,667	1,582
Accumulated Amortization	(858)	(754)
Net Book Value	809	828
Trade names
Information regarding other intangible assets
Gross Carrying Amount	102	102
Accumulated Amortization	0	0
Net Book Value	102	102
Contracts
Information regarding other intangible assets
Gross Carrying Amount	871	859
Accumulated Amortization	(76)	(60)
Net Book Value	795	799
Other
Information regarding other intangible assets
Gross Carrying Amount	104	106
Accumulated Amortization	(79)	(69)
Net Book Value	$ 25	$ 37

GOODWILL AND OTHER INTANGIBLE_5

GOODWILL AND OTHER INTANGIBLE ASSETS - Amortization (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Estimated future amortization of intangibles with finite useful lives
Total	$ 1,053
2,019	147
2,020	131
2,021	112
2,022	99
2,023	85
Later Years	479
Amortization expense	$ 185	$ 172	$ 152

INVESTMENTS AND OTHER ASSETS -

INVESTMENTS AND OTHER ASSETS - Components (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Marketable securities	$ 40	$ 56
Equity investments in unconsolidated healthcare entities	956	958
Total investments	996	1,014
Cash surrender value of life insurance policies	30	32
Long-term deposits	44	37
California provider fee program receivables	231	266
Land held for expansion, other long-term receivables and other assets	155	194
Investments and other assets	$ 1,456	$ 1,543

ACCUMULATED OTHER COMPREHENSI_3

ACCUMULATED OTHER COMPREHENSIVE LOSS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2018
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Adjustments for defined benefit plans	$ (223)	$ (170)
Foreign currency translation adjustments	0	(38)
Unrealized gains on investments	0	4
Accumulated other comprehensive loss	(223)	(204)
Tax effect allocated to adjustments for defined benefit plans	3	15
Tax effect allocated to adjustments for foreign currency translation adjustments	$ 3	5
Tax effect allocated to adjustments for unrealized gains on investments		$ 3
Accounting Standards Update 2018-02
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Cumulative effect of accounting change			$ 36
Accounting Standards Update 2016-01
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Cumulative effect of accounting change			$ 7

NET OPERATING REVENUES - Net Op

NET OPERATING REVENUES - Net Operating Revenue By Source (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Net operating revenues	$ 4,619	$ 4,489	$ 4,506	$ 4,699	$ 4,978	$ 4,586	$ 4,802	$ 4,813	$ 18,313	$ 19,179	$ 19,621
Hospital Operations and other
Disaggregation of Revenue [Line Items]
Net operating revenues									2,085	1,940	1,797
Hospital Operations and other | Health Care - Other Sources
Disaggregation of Revenue [Line Items]
Net operating revenues									28	31	24
Conifer
Disaggregation of Revenue [Line Items]
Net operating revenues									1,533	1,597	1,571
Operating Segments | Hospital Operations and other
Disaggregation of Revenue [Line Items]
Net operating revenues									15,285	16,260	16,904
Operating Segments | Hospital Operations and other:
Disaggregation of Revenue [Line Items]
Net operating revenues										16,260	16,904
Operating Segments | Ambulatory Care
Disaggregation of Revenue [Line Items]
Net operating revenues									2,085	1,940	1,797
Operating Segments | Conifer
Disaggregation of Revenue [Line Items]
Net operating revenues									1,533	1,597	1,571
Intersegment Eliminations
Disaggregation of Revenue [Line Items]
Net operating revenues									(590)	(618)	(651)
Continuing Operations
Disaggregation of Revenue [Line Items]
Net operating revenues									18,313	19,179	19,621
Continuing Operations | Operating Segments | Hospital Operations and other
Disaggregation of Revenue [Line Items]
Net operating revenues									15,285
Continuing Operations | Operating Segments | Hospital Operations and other | Physician practices revenues
Disaggregation of Revenue [Line Items]
Net operating revenues									1,097	1,209	1,201
Continuing Operations | Operating Segments | Hospital Operations and other | Health Care - Health Plans
Disaggregation of Revenue [Line Items]
Net operating revenues									14	110	482
Continuing Operations | Operating Segments | Hospital Operations and other | Health Care - Other Sources
Disaggregation of Revenue [Line Items]
Net operating revenues									93	112	94
Continuing Operations | Operating Segments | Ambulatory Care
Disaggregation of Revenue [Line Items]
Net operating revenues									2,085	1,940	1,797
Continuing Operations | Operating Segments | Conifer
Disaggregation of Revenue [Line Items]
Net operating revenues									1,533	1,597	1,571
Continuing Operations | Intersegment Eliminations
Disaggregation of Revenue [Line Items]
Net operating revenues									(590)	(618)	(651)
Acute Care Hospitals And Related Outpatient Facilities | Continuing Operations | Operating Segments | Hospital Operations and other | Medicare
Disaggregation of Revenue [Line Items]
Net operating revenues									2,882	3,243	3,386
Acute Care Hospitals And Related Outpatient Facilities | Continuing Operations | Operating Segments | Hospital Operations and other | Health Care, Patient Service - Medicare
Disaggregation of Revenue [Line Items]
Net operating revenues									1,294	1,304	1,346
Acute Care Hospitals And Related Outpatient Facilities | Continuing Operations | Operating Segments | Hospital Operations and other | Health Care, Patient Service - Managed Care
Disaggregation of Revenue [Line Items]
Net operating revenues									9,213	9,583	9,728
Acute Care Hospitals And Related Outpatient Facilities | Continuing Operations | Operating Segments | Hospital Operations and other | Health Care, Patient Service - Self-pay
Disaggregation of Revenue [Line Items]
Net operating revenues									96	91	63
Acute Care Hospitals And Related Outpatient Facilities | Continuing Operations | Operating Segments | Hospital Operations and other | Health Care, Patient Service - Indemnity And Other
Disaggregation of Revenue [Line Items]
Net operating revenues									596	608	604
Acute Care Hospitals And Related Outpatient Facilities | Continuing Operations | Operating Segments | Hospital Operations and other | Health Care, Patient Service, Excluding Physician Practices
Disaggregation of Revenue [Line Items]
Net operating revenues									$ 14,081	$ 14,829	$ 15,127

NET OPERATING REVENUES - Narrat

NET OPERATING REVENUES - Narrative (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Net operating revenues	$ 4,619	$ 4,489	$ 4,506	$ 4,699	$ 4,978	$ 4,586	$ 4,802	$ 4,813	$ 18,313	$ 19,179	$ 19,621
Conifer
Disaggregation of Revenue [Line Items]
Net operating revenues									$ 1,533	1,597	1,571
Revenue from other sources | Conifer
Disaggregation of Revenue [Line Items]
Percentage of net operating revenues related to Conifer generated by other services									7.00%
Restatement Adjustment
Disaggregation of Revenue [Line Items]
Net operating revenues									$ 24	$ 35	$ 54

NET OPERATING REVENUES - Net _2

NET OPERATING REVENUES - Net Operating Revenue Composition, Ambulatory Segment (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Net operating revenues	$ 4,619	$ 4,489	$ 4,506	$ 4,699	$ 4,978	$ 4,586	$ 4,802	$ 4,813	$ 18,313	$ 19,179	$ 19,621
Hospital Operations and other
Disaggregation of Revenue [Line Items]
Net operating revenues									2,085	1,940	1,797
Net patient service revenues | Hospital Operations and other
Disaggregation of Revenue [Line Items]
Net operating revenues									1,965	1,816	1,684
Management fees | Hospital Operations and other
Disaggregation of Revenue [Line Items]
Net operating revenues									92	93	89
Revenue from other sources | Hospital Operations and other
Disaggregation of Revenue [Line Items]
Net operating revenues									$ 28	$ 31	$ 24

NET OPERATING REVENUES - Net _3

NET OPERATING REVENUES - Net Operating Revenue Composition, Conifer Segment (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Disaggregation of Revenue [Line Items]
Net operating revenues	$ 4,619	$ 4,489	$ 4,506	$ 4,699	$ 4,978	$ 4,586	$ 4,802	$ 4,813	$ 18,313	$ 19,179	$ 19,621
Conifer
Disaggregation of Revenue [Line Items]
Net operating revenues									1,533	1,597	1,571
Tenet Healthcare Corp | Conifer | Revenue cycle services – Tenet
Disaggregation of Revenue [Line Items]
Net operating revenues									568	583	596
Tenet Healthcare Corp | Conifer | Health Care - Client Contracts - Other Services
Disaggregation of Revenue [Line Items]
Net operating revenues									22	35	55
Other Customers | Conifer | Revenue cycle services – Tenet
Disaggregation of Revenue [Line Items]
Net operating revenues									855	891	839
Other Customers | Conifer | Health Care - Client Contracts - Other Services
Disaggregation of Revenue [Line Items]
Net operating revenues									$ 88	$ 88	$ 81

NET OPERATING REVENUES - Perfor

NET OPERATING REVENUES - Performance Obligation (Details) - Conifer $ in Millions	Dec. 31, 2018USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 7,736
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	585
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	584
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	581
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	581
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	581
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 4,824

NET OPERATING REVENUES - Perf_2

NET OPERATING REVENUES - Performance Obligation 2 (Details) $ in Millions	Dec. 31, 2018USD ($)
Conifer
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, amount	$ 7,736

NET OPERATING REVENUES - Perf_3

NET OPERATING REVENUES - Performance Obligation Timing of Satisfaction (Details)	Dec. 31, 2018
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, remaining performance obligation, expected timing of satisfaction, period

PROPERTY AND PROFESSIONAL AND_2

PROPERTY AND PROFESSIONAL AND GENERAL LIABILITY INSURANCE (Details) $ in Millions	9 Months Ended
	Dec. 31, 2018USD ($)
Insurance coverage
Insurance coverage, aggregate limit	$ 850
Floods
Insurance coverage
Insurance, maximum coverage per incident	100
Earthquakes
Insurance coverage
Insurance, maximum coverage per incident	200
Windstorms
Insurance coverage
Insurance, maximum coverage per incident	200
Fires and other perils
Insurance coverage
Insurance, maximum coverage per incident	$ 850
Floods, earthquakes and windstorms
Insurance coverage
Insurance deductible percentage	5.00%
Insurance deductible	$ 25
New Madrid fault earthquakes
Insurance coverage
Insurance deductible percentage	2.00%
Insurance deductible	$ 25
Fires and certain other covered losses
Insurance coverage
Insurance deductible	$ 1

PROPERTY AND PROFESSIONAL AND_3

PROPERTY AND PROFESSIONAL AND GENERAL LIABILITY INSURANCE - Professional and General Liability Reserves (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Insurance coverage
Risk-free discount rate	2.59%	2.33%
Professional and general liability reserves
Insurance coverage
Self insurance reserve	$ 882	$ 854
Loss contingency discount rate, maturity rate period	7 years		7 years
Risk-free discount rate	2.59%	2.33%	2.25%
Professional and general liability reserves | Other operating expense, net
Insurance coverage
Malpractice expense	$ 388	$ 303	$ 281

CLAIMS AND LAWSUITS (Details)

CLAIMS AND LAWSUITS (Details) $ in Millions	1 Months Ended	12 Months Ended
	Jun. 30, 2006hospital	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Jan. 31, 2017lawsuit
Shareholder derivative litigation
Loss Contingencies
Number of consolidated lawsuits | lawsuit					2
Maderazo V. VHS San Antonio
Loss Contingencies
Number of hospitals | hospital	3
Pending Litigation
Loss Contingencies
Gain (loss) total related to litigation settlement		$ (38)	$ (23)	$ (293)
Pending Litigation | Clinica De La Mama Matters
Loss Contingencies
Gain (loss) total related to litigation settlement				$ (278)

CLAIMS AND LAWSUITS - Reconcili

CLAIMS AND LAWSUITS - Reconciliations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Loss Contingencies
Litigation and investigation costs	$ (38)	$ (23)	$ (293)
Claims, lawsuits, and regulatory proceedings
Loss Contingencies
Litigation and investigation costs	(38)	(23)	(293)
Loss Contingency Accrual [Roll Forward]
Litigation reserve, Balances at Beginning of Period	12	12	299
Litigation and Investigation Costs	38	23	293
Cash Payments	(41)	(23)	(582)
Other	(1)	0	2
Litigation reserve, Balances at End of Period	$ 8	$ 12	12
Clinica De La Mama Matters | Claims, lawsuits, and regulatory proceedings
Loss Contingency Accrual [Roll Forward]
Litigation and Investigation Costs			$ 278

REDEEMABLE NONCONTROLLING INT_3

REDEEMABLE NONCONTROLLING INTERESTS IN EQUITY OF CONSOLIDATED SUBSIDIARIES (Details) - USD ($) $ in Millions	Jul. 03, 2017	Apr. 30, 2018	Jul. 31, 2017	Apr. 30, 2016	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2016
Interests acquired and other disclosures
Redeemable noncontrolling interest					$ 1,420	$ 1,866
United Surgical Partners International
Interests acquired and other disclosures
Payment contributed to joint venture	$ 716	$ 630	$ 716	$ 127
Joint venture, ownership percentage	80.00%	15.00%	80.00%	56.30%			50.10%
United Surgical Partners International | Put option
Interests acquired and other disclosures
Equity necessary for joint venture					5.00%
United Surgical Partners International | Redeemable noncontrolling interests
Interests acquired and other disclosures
Payment contributed to joint venture				$ 127
Joint venture, ownership percentage		95.00%		56.30%
Baylor University Medical Center | Put option | Maximum
Interests acquired and other disclosures
Equity necessary for joint venture					33.30%

REDEEMABLE NONCONTROLLING INT_4

REDEEMABLE NONCONTROLLING INTERESTS IN EQUITY OF CONSOLIDATED SUBSIDIARIES - Changes in Redeemable Noncontrolling Interests (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Changes in redeemable noncontrolling interests in equity of consolidated subsidiaries
Distributions paid to noncontrolling interests	$ (148)	$ (123)	$ (111)
Redeemable noncontrolling interests
Changes in redeemable noncontrolling interests in equity of consolidated subsidiaries
Balances at beginning of period	1,866	2,393
Net income	190	239
Distributions paid to noncontrolling interests	(142)	(128)
Accretion of redeemable noncontrolling interests	173	33
Purchases and sales of businesses and noncontrolling interests, net	(667)	(671)
Balances at end of period	$ 1,420	$ 1,866	$ 2,393

REDEEMABLE NONCONTROLLING INT_5

REDEEMABLE NONCONTROLLING INTERESTS IN EQUITY OF CONSOLIDATED SUBSIDIARIES - Segment Details (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Hospital Operations and other
Changes in redeemable noncontrolling interests in equity of consolidated subsidiaries
Redeemable noncontrolling interests balances	$ 431	$ 519
Net income	(25)	18
Ambulatory Care
Changes in redeemable noncontrolling interests in equity of consolidated subsidiaries
Redeemable noncontrolling interests balances	713	1,137
Net income	151	170
Conifer
Changes in redeemable noncontrolling interests in equity of consolidated subsidiaries
Redeemable noncontrolling interests balances	276	210
Net income	$ 64	$ 51

INCOME TAXES - Provision and De

INCOME TAXES - Provision and Deferred Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Current tax expense (benefit):
Federal	$ (6)	$ (4)	$ 12
State	33	23	14
Total	27	19	26
Deferred tax expense (benefit):
Federal	159	202	34
State	(10)	(2)	7
Total	149	200	41
Income tax expense (benefit)	$ 176	$ 219	$ 67

INCOME TAXES - Federal Tax Reco

INCOME TAXES - Federal Tax Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Decrease in valuation allowance due to changes based on expiration or worthlessness of unutilized state net operating loss carryovers	$ 9	$ 28	$ 24
Income tax benefit, reduction in valuation allowance of expired or worthless operating loss carryforwards	9
Foreign pretax loss	6	70
Reconciliation between reported income tax expense (benefit) and income taxes calculated by the statutory federal income tax rate
Tax expense (benefit) at statutory federal rate of 21% in 2018 (35% in 2017 and 2016)	134	(35)	87
State income taxes, net of federal income tax benefit	23	4	16
Expired state net operating losses, net of federal income tax benefit	9	28	35
Tax attributable to noncontrolling interests	(70)	(113)	(106)
Nondeductible goodwill	8	109	29
Nontaxable gains	0	0	(11)
Nondeductible litigation costs	0	0	37
Impact of decrease in federal tax rate on deferred taxes	(1)	246	0
Reversal of permanent reinvestment assumption and other adjustments related to divestiture of foreign subsidiary	(6)	(30)	0
Stock-based compensation tax deficiencies	5	15	0
Changes in valuation allowance (including impact of decrease in federal tax rate)	76	0	(25)
Change in tax contingency reserves, including interest	(1)	(6)	(9)
Prior-year provision to return adjustments and other changes in deferred taxes	(5)	4	12
Other items	4	(3)	2
Income tax expense (benefit)	$ 176	$ 219	$ 67

INCOME TAXES - Tax Cuts and Job

INCOME TAXES - Tax Cuts and Jobs Act (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Tax cuts and jobs act of 2017, incomplete accounting, change in tax rate, deferred tax asset, provisional income tax (expense) benefit			$ 252
Tax cuts and jobs act of 2017, incomplete accounting, change in tax rate, deferred tax asset, change in valuation allowance, provisional income tax (expense) benefit	$ 251		6
Impact of decrease in federal tax rate on deferred taxes		$ (1)	$ 246	$ 0

INCOME TAXES - Components of De

INCOME TAXES - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets
Reserves related to discontinued operations and restructuring charges	$ 24	$ 15
Receivables (doubtful accounts and adjustments)	155	134
Accruals for retained insurance risks	205	225
Other long-term liabilities	39	97
Benefit plans	255	268
Other accrued liabilities	32	42
Interest expense limitation	89
Net operating loss carryforwards	266	399
Stock-based compensation	24	27
Other items	88	142
Deferred tax assets, gross	1,177	1,349
Valuation allowance	(148)	(72)	$ (72)
Deferred tax assets, net	1,029	1,277
Liabilities
Depreciation and fixed-asset differences	297	411
Deferred gain on debt exchanges	0	6
Intangible assets	341	330
Investments and other assets	83	79
Other items	32	32
Deferred tax liabilities, total	753	858
Reconciliation of the deferred tax assets and liabilities
Deferred income tax assets	312	455
Deferred tax liabilities	(36)	(36)
Net deferred tax asset	$ 276	$ 419

INCOME TAXES - Valuation Allowa

INCOME TAXES - Valuation Allowances and Unrecognized Tax Benefits (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
INCOME TAXES
Increase (decrease) in valuation allowance against deferred tax assets	$ 76,000,000	$ 0
Increase in valuation allowance due to limitations on deductions of interest expense	89,000,000
Decrease in valuation allowance due to changes based on expiration or worthlessness of unutilized state net operating loss carryovers	9,000,000	28,000,000	$ 24,000,000
Increase in valuation allowance due to changes in expected realizability of deferred tax assets	4,000,000	22,000,000
Valuation allowance	148,000,000	72,000,000	72,000,000
Increase in valuation allowance due to changes in federal tax rate		6,000,000
Changes in unrecognized tax benefits
Beginning balance	46,000,000	35,000,000
Ending balance	45,000,000	46,000,000	35,000,000
Unrecognized tax benefits which, if recognized, would impact effective tax rate	43,000,000	44,000,000	32,000,000
Current income tax benefit due to increase in liabilities for uncertain tax positions	1,000,000	(5,000,000)	9,000,000
Uncertain tax positions, interest and penalties related to continuing operations	1,000,000
Total accrued interest and penalties on unrecognized tax benefits	3,000,000
Continuing Operations
Changes in unrecognized tax benefits
Beginning balance	46,000,000	35,000,000	40,000,000
Additions for prior-year tax positions		31,000,000	2,000,000
Reductions due to a lapse of statute of limitations	(1,000,000)	(5,000,000)	(7,000,000)
Reductions for tax positions of prior years		(15,000,000)
Ending balance	$ 45,000,000	$ 46,000,000	$ 35,000,000

INCOME TAXES - NOL (Details)

INCOME TAXES - NOL (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Operating loss carryforwards
Unrecognized federal and state tax benefits and reserves for interest and penalties, which may decrease in the next 12 months	$ 10
Deferred tax benefit, net of valuation allowance and federal tax impact, associated with NOL carryforwards	266	$ 399
Federal
Operating loss carryforwards
Net operating loss carryforwards subject to expiration	1,000
State
Operating loss carryforwards
Net operating loss carryforwards subject to expiration	3,100
Deferred tax benefit, net of valuation allowance and federal tax impact, associated with NOL carryforwards	$ 22

INCOME TAXES - Tax Credit Carry

INCOME TAXES - Tax Credit Carryforwards (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)
Tax credits
Rolling period during which certain ownership changes limit ability of the entity for utilization of NOL carryforwards	3 years
Percentage of shareholders, purchase or sale of stock by them is considered as ownership change	5.00%
Maximum increase in percentage points of the ownership of the 5% shareholders in a given period to enable the full use of NOL carryfowards	50.00%
General business
Tax credits
Tax credits carryforwards	$ 26

EARNINGS (LOSS) PER COMMON SH_3

EARNINGS (LOSS) PER COMMON SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net Income Available (Loss Attributable) to Common Shareholders (Numerator)
Net loss attributable to Tenet Healthcare Corporation common shareholders for basic earnings (loss) per share	$ 108	$ (704)	$ (187)
Net loss attributable to Tenet Healthcare Corporation common shareholders for diluted earnings (loss) per share	$ 108	$ (704)	$ (187)
Weighted Average Shares (Denominator)
Net loss attributable to Tenet Healthcare Corporation common shareholders for basic earnings (loss) per share (in shares)	102,110	100,592	99,321
Effect of dilutive stock options, restricted stock units and deferred compensation units (in shares)	1,771	0	0
Net loss attributable to Tenet Healthcare Corporation common shareholders for diluted earnings (loss) per share (in shares)	103,881	100,592	99,321
Per-Share Amount
Net loss attributable to Tenet Healthcare Corporation common shareholders for basic earnings (loss) per share (in dollars per share)	$ 1.06	$ (7)	$ (1.88)
Effect of dilutive stock options, restricted stock units, and deferred compensation units (in dollars per share)	(0.02)	0	0
Net loss attributable to Tenet Healthcare Corporation common shareholders for diluted earnings (loss) per share (in dollars per share)	$ 1.04	$ (7)	$ (1.88)

EARNINGS (LOSS) PER COMMON SH_4

EARNINGS (LOSS) PER COMMON SHARE - Antidilutive securities (Details) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Employee stock options, restricted stock units and deferred compensation units
Antidilutive securities
Anti-dilutive securities excluded from computation of earnings per share (in shares)	788	1,421

FAIR VALUE MEASUREMENTS (Detail

FAIR VALUE MEASUREMENTS (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)hospital	Dec. 31, 2017USD ($)	Dec. 31, 2016USD ($)hospital
Fair value of assets and liabilities measured on recurring basis
Long-lived assets held for sale	$ 39	$ 456
Long-lived assets held and used	130	0
Other than temporarily impaired equity method investments		113
Impairment charges	$ 40	364	$ 54
Number of hospitals with impairment charges | hospital	2		4
Investments impairment	$ 9	31
Impairment charges related to write-down of long-lived assets	$ 4	$ 7
Estimated fair value of the long-term debt instrument as a percentage of carrying value	97.30%	100.20%
Continuing Operations
Fair value of assets and liabilities measured on recurring basis
Write-down assets held for sale	$ 24
Impairment charges related to write-down of long-lived assets		$ 364
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair value of assets and liabilities measured on recurring basis
Long-lived assets held for sale	0	0
Long-lived assets held and used	0	0
Other than temporarily impaired equity method investments		0
Significant Other Observable Inputs (Level 2)
Fair value of assets and liabilities measured on recurring basis
Long-lived assets held for sale	39	456
Long-lived assets held and used	130	0
Other than temporarily impaired equity method investments		113
Significant Unobservable Inputs (Level 3)
Fair value of assets and liabilities measured on recurring basis
Long-lived assets held for sale	0	0
Long-lived assets held and used	$ 0	0
Other than temporarily impaired equity method investments		$ 0

ACQUISITIONS (Details)

ACQUISITIONS (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018USD ($)business	Dec. 31, 2017USD ($)business	Dec. 31, 2016USD ($)	Dec. 31, 2016USD ($)hospital	Dec. 31, 2016USD ($)business
United Surgical Partners International
Business Acquisition
Number of business acquisitions	10	8		28	3
Number of consolidated microhospitals | hospital				5
Series of individual business acquisitions
Business Acquisition
Fair value of consideration conveyed	$ 113	$ 50	$ 117	$ 117	$ 117
Series of individual business acquisitions | United Surgical Partners International
Business Acquisition
Consideration conveyed in the acquisition	$ 113	$ 50	$ 117

ACQUISITIONS - Purchase Price A

ACQUISITIONS - Purchase Price Allocation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Final purchase price allocations
Goodwill	$ 7,281	$ 7,018
Series of individual business acquisitions
Final purchase price allocations
Current assets	6	7	$ 51
Property and equipment	19	9	38
Other intangible assets	9	8	7
Goodwill	220	91	464
Other long-term assets, including previously held equity method investments	(18)	(3)	(56)
Current liabilities	0	(8)	(30)
Long-term liabilities	(15)	(2)	(15)
Redeemable noncontrolling interests in equity of consolidated subsidiaries	(21)	(29)	(190)
Noncontrolling interests	(85)	(18)	(119)
Cash paid, net of cash acquired	(113)	(50)	(117)
Gains on consolidations	$ 2	$ 5	$ 33

ACQUISITIONS - Pro Forma (Detai

ACQUISITIONS - Pro Forma (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Business Acquisition
Goodwill	$ 7,281	$ 7,018
Acquisition-related transaction costs	10	6	$ 20
Series of individual business acquisitions
Business Acquisition
Goodwill	220	91	464
Acquisition-related transaction costs		6	20
Gains on consolidations	2	5	33
Hospital Operations and other
Business Acquisition
Goodwill	2,980	2,976	3,373
Hospital Operations and other | Series of individual business acquisitions
Business Acquisition
Goodwill	1
Ambulatory Care
Business Acquisition
Goodwill	3,696	$ 3,437	$ 3,447
Ambulatory Care | Series of individual business acquisitions
Business Acquisition
Goodwill	$ 219

SEGMENT INFORMATION - General I

SEGMENT INFORMATION - General Information and Customer Concentration (Details)	8 Months Ended	12 Months Ended
	Aug. 16, 2018hospital	Dec. 31, 2018hospitalstate
SEGMENT INFORMATION
Number of hospitals owned by subsidiaries		68
Number of states in which entity operates | state		10
Number of surgical hospitals		23
Minimum | Conifer
SEGMENT INFORMATION
Number of Tenet and non-Tenet Hospitals and other health care organizations to which Conifer provided revenue cycle services		750
United Surgical Partners International
SEGMENT INFORMATION
Number of states in which entity operates		27
Number of ambulatory surgery centers		255
Number of urgent care centers		36
Number of diagnostic imaging centers		23
Number of surgical hospitals		23
European Surgical Partners Ltd | United Surgical Partners International
SEGMENT INFORMATION
Number of outpatient centers	9
United Surgical Partners International | Ambulatory Care
SEGMENT INFORMATION
Ownership percentage of subsidiary		95.00%
Conifer Health Solutions, LLC | Conifer
SEGMENT INFORMATION
Ownership percentage of subsidiary		76.20%
Disposal group, held-for-sale, not discontinued operations
SEGMENT INFORMATION
Number of hospitals divested		3

SEGMENT INFORMATION - Reconcili

SEGMENT INFORMATION - Reconciling Items (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
SEGMENT INFORMATION
Assets:	$ 22,409				$ 23,385				$ 22,409	$ 23,385	$ 24,701
Capital expenditures:									617	707	875
Net operating revenues	4,619	$ 4,489	$ 4,506	$ 4,699	4,978	$ 4,586	$ 4,802	$ 4,813	18,313	19,179	19,621
Equity in earnings of unconsolidated affiliates									150	144	131
Adjusted EBITDA									2,560	2,444	2,478
Depreciation and amortization									802	870	850
Adjusted EBITDA and other reconciling items
Adjusted EBITDA									2,560	2,444	2,478
Income (loss) from divested and closed businesses (i.e., the Company’s health plan businesses)									9	(41)	(37)
Depreciation and amortization									(802)	(870)	(850)
Impairment and restructuring charges, and acquisition-related costs									(209)	(541)	(202)
Litigation and investigation costs									(38)	(23)	(293)
Interest expense									(1,004)	(1,028)	(979)
Gain (loss) from early extinguishment of debt									1	(164)	0
Other non-operating expense, net									(5)	(22)	(20)
Net gains on sales, consolidation and deconsolidation of facilities									127	144	151
Income (loss) from continuing operations, before income taxes									639	(101)	248
Inter-segment eliminations
SEGMENT INFORMATION
Net operating revenues									(590)	(618)	(651)
Hospital Operations and other
SEGMENT INFORMATION
Assets:	15,684				16,466				15,684	16,466	17,871
Net operating revenues									2,085	1,940	1,797
Hospital Operations and other | Operating segments
SEGMENT INFORMATION
Capital expenditures:									527	625	799
Net operating revenues									15,285	16,260	16,904
Equity in earnings of unconsolidated affiliates									10	4	9
Adjusted EBITDA									1,411	1,462	1,586
Depreciation and amortization									685	736	709
Adjusted EBITDA and other reconciling items
Adjusted EBITDA									1,411	1,462	1,586
Depreciation and amortization									(685)	(736)	(709)
Ambulatory Care
SEGMENT INFORMATION
Assets:	5,711				5,822				5,711	5,822	5,722
Ambulatory Care | Operating segments
SEGMENT INFORMATION
Capital expenditures:									68	60	51
Net operating revenues									2,085	1,940	1,797
Equity in earnings of unconsolidated affiliates									140	140	122
Adjusted EBITDA									792	699	615
Depreciation and amortization									68	84	91
Adjusted EBITDA and other reconciling items
Adjusted EBITDA									792	699	615
Depreciation and amortization									(68)	(84)	(91)
Conifer
SEGMENT INFORMATION
Assets:	$ 1,014				$ 1,097				1,014	1,097	1,108
Net operating revenues									1,533	1,597	1,571
Conifer | Operating segments
SEGMENT INFORMATION
Capital expenditures:									22	22	25
Net operating revenues									1,533	1,597	1,571
Adjusted EBITDA									357	283	277
Depreciation and amortization									49	50	50
Adjusted EBITDA and other reconciling items
Adjusted EBITDA									357	283	277
Depreciation and amortization									(49)	(50)	(50)
Conifer | Operating segments | Tenet
SEGMENT INFORMATION
Net operating revenues									590	618	651
Conifer | Operating segments | Other clients
SEGMENT INFORMATION
Net operating revenues									$ 943	$ 979	$ 920

RECENT ACCOUNTING STANDARDS Nar

RECENT ACCOUNTING STANDARDS Narrative (Details) - Accounting Standards Update 2016-02 - Subsequent Event $ in Millions	Jan. 01, 2019USD ($)
Minimum
Lessee, Lease, Description [Line Items]
Operating lease asset	$ 750
Operating lease liability	750
Maximum
Lessee, Lease, Description [Line Items]
Operating lease asset	800
Operating lease liability	$ 800

SUBSEQUENT EVENTS (Details)

SUBSEQUENT EVENTS (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Jun. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Feb. 05, 2019	Nov. 30, 2018
Subsequent events
Loss (gain) from early extinguishment of debt			$ (1,000,000)	$ 164,000,000	$ 0
6.750% due 2020
Subsequent events
Interest rate, stated percentage			6.75%
7.500% due 2022
Subsequent events
Interest rate, stated percentage			7.50%
5.500% due 2019
Subsequent events
Interest rate, stated percentage			5.50%
Senior Notes
Subsequent events
Loss (gain) from early extinguishment of debt		$ 26,000,000
Senior Notes | 5.500% due 2019
Subsequent events
Repurchased face amount			$ 22,000,000				$ 10,000,000
Subsequent Event | 6.250% due 2027
Subsequent events
Interest rate, stated percentage						6.25%
Subsequent Event | 7.500% due 2022
Subsequent events
Interest rate, stated percentage						7.50%
Subsequent Event | 5.500% due 2019
Subsequent events
Interest rate, stated percentage						5.50%
Subsequent Event | Senior Notes | 6.250% due 2027
Subsequent events
Senior notes sold						$ 1,500,000,000
Subsequent Event | Senior Notes | 6.750% due 2020
Subsequent events
Interest rate, stated percentage						6.75%
Repurchased face amount						$ 300,000,000
Subsequent Event | Senior Notes | 7.500% due 2022
Subsequent events
Repurchased face amount						750,000,000
Subsequent Event | Senior Notes | 5.500% due 2019
Subsequent events
Repurchased face amount						$ 468,000,000
Scenario, Forecast
Subsequent events
Loss (gain) from early extinguishment of debt	$ 47,000,000

Supplemental Financial Inform_3

Supplemental Financial Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Condensed Financial Information Disclosure [Abstract]
Net operating revenues	$ 4,619	$ 4,489	$ 4,506	$ 4,699	$ 4,978	$ 4,586	$ 4,802	$ 4,813	$ 18,313	$ 19,179	$ 19,621
Net income	102	65	108	191	(99)	(289)	32	36	466	(320)	176
Net income available (loss attributable) to Tenet Healthcare Corporation common shareholders	$ (5)	$ (9)	$ 26	$ 99	$ (229)	$ (367)	$ (55)	$ (53)	$ 111	$ (704)	$ (192)
Income available (loss attributable) per share to Tenet Healthcare Corporation common shareholders, basic (in usd per share)	$ (0.04)	$ (0.09)	$ 0.25	$ 0.98	$ (2.27)	$ (3.64)	$ (0.55)	$ (0.53)	$ 1.09	$ (7)	$ (1.93)
Income available (loss attributable) per share to Tenet Healthcare Corporation common shareholders, diluted (in usd per share)	$ (0.04)	$ (0.09)	$ 0.25	$ 0.96	$ (2.27)	$ (3.64)	$ (0.55)	$ (0.53)	$ 1.07	$ (7)	$ (1.93)

SCHEDULE II-VALUATION AND QUA_2

SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for doubtful accounts:
Movement in valuation and qualifying accounts
Balance at Beginning of Period	$ 898	$ 1,031	$ 887
Costs and Expenses	0	1,434	1,451
Deductions	0	(1,445)	(1,307)
Other Items	(898)	(122)	0
Balance at End of Period	0	898	1,031
Valuation allowance for deferred tax assets:
Movement in valuation and qualifying accounts
Balance at Beginning of Period	72	72	96
Costs and Expenses		0
Costs and Expenses	76		(24)
Deductions	0	0	0
Other Items	0	0	0
Balance at End of Period	$ 148	$ 72	$ 72

Uncategorized Items - thc-20181

Label	Element	Value
Hospital Operations And Other Total Prior To Inter-Segment Eliminations [Member]
Contract with Customer, Asset, Net, Current	us-gaap_ContractWithCustomerAssetNetCurrent	$ 171,000,000
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	43,000,000
AOCI Attributable to Parent [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	(43,000,000)
Accounting Standards Update 2016-09 [Member] | Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 56,000,000