PROPERTY AND PROFESSIONAL AND GENERAL LIABILITY INSURANCE (Details) $ in Millions	9 Months Ended
Sep. 30, 2016 USD ($)
Insurance coverage
Insurance coverage, aggregate limit	$ 600
Flood and Earthquake
Insurance coverage
Insurance, maximum coverage per incident	100
Windstorms
Insurance coverage
Insurance, maximum coverage per incident	$ 200
Flood, earthquake and windstorm
Insurance coverage
Insurance deductible (as a percentage)	5.00%
Flood, earthquake and windstorm \| Maximum
Insurance coverage
Insurance deductible	$ 25
New Madrid fault earthquakes
Insurance coverage
Insurance deductible (as a percentage)	2.00%
New Madrid fault earthquakes \| Maximum
Insurance coverage
Insurance deductible	$ 25
Fire and other perils
Insurance coverage
Insurance, maximum coverage per incident	600
Fire and other perils \| Minimum
Insurance coverage
Insurance deductible	$ 1

No definition available.

Name:	thc_InsuranceCoverageLineItems
Namespace Prefix:	thc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of risk retained by the entity before the insurance arrangement begins to provide coverage.

+ References

No definition available.

+ Details

Name:	thc_MalpracticeInsuranceDeductiblePercentage
Namespace Prefix:	thc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Annual coverage limit provided by the insurance arrangement for malpractice claims.

+ References

No definition available.

+ Details

Name:	us-gaap_MalpracticeInsuranceAnnualCoverageLimit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of risk retained by the entity before the insurance arrangement begins to provide coverage.

+ References

No definition available.

+ Details

Name:	us-gaap_MalpracticeInsuranceDeductible1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Maximum coverage per malpractice claim provided by the insurance arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 450
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6491354&loc=d3e6049-115624

+ Details

Name:	us-gaap_MalpracticeInsuranceMaximumCoveragePerIncident
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_LiabilityForCatastropheClaimsByCatastrophicEventAxis=thc_FloodAndEarthquakeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LiabilityForCatastropheClaimsByCatastrophicEventAxis=thc_WindstormsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LiabilityForCatastropheClaimsByCatastrophicEventAxis=thc_FloodEarthquakeAndWindstormMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LiabilityForCatastropheClaimsByCatastrophicEventAxis=us-gaap_EarthquakeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LiabilityForCatastropheClaimsByCatastrophicEventAxis=thc_FireAndOtherPerilsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: