-- None. No documentation exists for this element. --

No definition available.

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- Definition

Loss Contingency, General Damages Sought, Value

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Loss Contingency, Punitive Damages Sought, Value

+ References

No definition available.

+ Details

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Namespace Prefix:	clh_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

The estimated minimum amount of possible loss from the federal and state enforcement actions.

+ References

No definition available.

+ Details

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Namespace Prefix:	clh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

This element represents the number of municipalities other than Ville Mercier that filed legal proceedings against the Mercier Subsidiary.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

The number of permits that are granted by the government in relation to environmental liabilities.

+ References

No definition available.

+ Details

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Namespace Prefix:	clh_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349

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-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

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- Definition

Amount of loss contingency liability.

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- Definition

The number of claims settled and dismissed during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
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- Definition

Number of pending claims pertaining to a loss contingency.

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COMMITMENTS AND CONTINGENCIES (Legal and Administrative Proceedings) (Details) $ in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) proceeding claim	Dec. 31, 2012 CAD ($)	Dec. 31, 1999 municipality	Dec. 31, 1968 permit	Dec. 31, 2018 USD ($) proceeding	Dec. 31, 2017 USD ($)
Legal and Administrative Proceedings
Reserves	$ 26,000				$ 25,400
Remedial Liability	$ 114,173				121,017	$ 124,468
Safety-Kleen
Legal and Administrative Proceedings
Number of proceedings \| proceeding	55
Loss contingency, claims settled and dismissed, claims \| claim	27
Legal and Administrative Proceedings
Legal and Administrative Proceedings
Remedial Liability	$ 18,400				17,900
Ville Mercier
Legal and Administrative Proceedings
Number of permits issued by government, for dumping organic liquid \| permit				2
Number of neighboring municipalities filing separate legal proceedings against the Mercier subsidiary and the government of Quebec \| municipality			3
General damages sought		$ 2.9
Punitive damages sought		$ 10.0
Federal, State, and Provincial Enforcement Actions
Legal and Administrative Proceedings
Reserves relating to legal and administrative proceedings	$ 7,600				$ 7,500
Number of proceedings \| proceeding	12				10