GUARANTEES (Details) $ in Millions	Sep. 30, 2018 USD ($)
Income and Revenue Collection Guarantee
GUARANTEES
Maximum potential amount of future payments under guarantees	$ 186
Income and Revenue Collection Guarantee \| Other current liabilities
GUARANTEES
Liability for the fair value of guarantees	138
Guaranteed Investees Of Third Parties
GUARANTEES
Liability for the fair value of guarantees	27
Guaranteed Investees Of Third Parties \| Other current liabilities
GUARANTEES
Guarantee obligations for consolidated subsidiaries	$ 18

The carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees which pertains to the entity's consolidated subsidiaries

No definition available.

+ Details

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Namespace Prefix:	thc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248

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- Definition

Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12201-110248

+ Details

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- Details

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- Details

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- Details

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