CLOSURE AND POST-CLOSURE LIABILITIES (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
Sep. 30, 2013
Changes to post-closure liabilities
Balance at January 1, 2013	$ 54,248
Liabilities assumed in acquisitions	659
Adjustments during the measurement period related to acquisitions	(10,201)
New asset retirement obligations	3,321
Accretion	3,536
Changes in estimates recorded to statement of income	(299)
Changes in estimates recorded to balance sheet	299
Expenditures	(3,837)
Currency translation and other	(232)
Balance at September 30, 2013	47,494
Credit-adjusted risk-free rate (as a percent)	6.60%
Landfill Retirement Liability
Changes to post-closure liabilities
Balance at January 1, 2013	26,658
Liabilities assumed in acquisitions	0
Adjustments during the measurement period related to acquisitions	0
New asset retirement obligations	3,321
Accretion	2,255
Changes in estimates recorded to statement of income	(398)
Changes in estimates recorded to balance sheet	299
Expenditures	(3,527)
Currency translation and other	(152)
Balance at September 30, 2013	28,456
Non-Landfill Retirement Liability
Changes to post-closure liabilities
Balance at January 1, 2013	27,590
Liabilities assumed in acquisitions	659
Adjustments during the measurement period related to acquisitions	(10,201)
New asset retirement obligations
Accretion	1,281
Changes in estimates recorded to statement of income	99
Changes in estimates recorded to balance sheet	0
Expenditures	(310)
Currency translation and other	(80)
Balance at September 30, 2013	$ 19,038

Asset Retirement Obligation, Adjustments Related to Acquisitions

No definition available.

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

- Definition

The amount of change in the asset retirement obligation, during the current period, for changes in estimates recorded in the statement of income.

+ References

No definition available.

+ Details

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

- Definition

The total amount of the increase or decrease in the amount of asset retirement obligations for the period that is associated with foreign currency translation (to the extent that the entity accounts for the foreign currency effects as a separate component of the change in the liability) and other asset retirement obligations.

+ References

No definition available.

+ Details

Name:	clh_AssetRetirementObligationForeignCurrencyTranslationAndOther
Namespace Prefix:	clh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the amount of change in the asset retirement obligation, during the current period for other changes in estimates recorded in the balance sheet.

+ References

No definition available.

+ Details

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

- Definition

Asset Retirement Obligations, Liabilities Assumed in Acquisitions

+ References

No definition available.

+ Details

Name:	clh_AssetRetirementObligationsLiabilitiesAssumedInAcquisitions
Namespace Prefix:	clh_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The rate applied to the undiscounted amount of new asset retirement obligations that are expected to arrive at the present value and that are recorded as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	clh_CreditAdjustedRiskFreeRate
Namespace Prefix:	clh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 3, 10, 22

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Asset Retirement Obligation

-URI http://asc.fasb.org/extlink&oid=6505190

+ Details

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

- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 22

-Subparagraph c(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 13, 14

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

- Definition

Amount of asset retirement obligations incurred during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 22

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_AssetRetirementObligationLiabilitiesIncurred
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 143

-Paragraph 22

-Subparagraph c(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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

- Details

Name:	us-gaap_AssetRetirementObligationRollForwardAnalysisRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration