-- 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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- Definition

Loss Contingency, Punitive Damages Sought, Value

+ References

No definition available.

+ Details

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

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

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

Amount of loss contingency liability.

+ 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=121557415&loc=d3e14326-108349

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349

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- Definition

Number of pending claims pertaining to a loss contingency.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
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COMMITMENTS AND CONTINGENCIES - Legal and Administrative Proceedings (Details) $ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) proceeding claim	Dec. 31, 2012 CAD ($)	Dec. 31, 1999 municipality	Dec. 31, 1968 permit	Dec. 31, 2020 USD ($)
Legal and Administrative Proceedings
Loss contingency accrual	$ 36.1				$ 29.8
Product Liability Cases
Legal and Administrative Proceedings
Number of proceedings \| proceeding	61
Loss contingency, claims settled and dismissed, claims \| claim	21
Legal and Administrative Proceedings
Legal and Administrative Proceedings
Loss contingency accrual	$ 24.1				24.0
Federal, State, and Provincial Enforcement Actions
Legal and Administrative Proceedings
Loss contingency accrual	$ 12.0				$ 5.8
Number of proceedings \| proceeding	2
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