Debt Instrument, Floor Interest Rate

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Debt Instrument, Prepayment Premium Rate, Percentage

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
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

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

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtWeightedAverageInterestRate
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Nominal or face amount used to calculate payment on derivative.

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+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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+ Details

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

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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- Details

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- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=clh_A2028TermLoansMember
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- Details

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- Details

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- Details

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FINANCING ARRANGEMENTS - Additional Information (Details) - USD ($)	Oct. 08, 2021	Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Debt fair value		$ 1,600,000,000	$ 1,600,000,000
Interest rate swap, liability		23,500,000	33,600,000
Interest Rate Swap
Debt Instrument [Line Items]
Notional amount of interest rate swap agreements		350,000,000
Secured debt \| 2028 Term Loans \| Subsequent Event
Debt Instrument [Line Items]
Debt prepayment premium rate, percentage	1.00%
Secured debt \| 2028 Term Loans \| Subsequent Event \| HydroChemPSC
Debt Instrument [Line Items]
Debt Instrument, face amount	$ 1,000,000,000
Net proceeds from the company’s issuance	$ 983,000,000
Secured debt \| 2028 Term Loans \| Eurodollar \| Subsequent Event
Debt Instrument [Line Items]
Debt, basis spread on variable rate	2.00%
Debt, floor interest rate	0.00%
Secured debt \| 2028 Term Loans \| Base Rate \| Subsequent Event
Debt Instrument [Line Items]
Debt, basis spread on variable rate	1.00%
Debt, floor interest rate	1.00%
Secured debt \| Secured senior term loans due June 30, 2024 ("2024 Term Loans")
Debt Instrument [Line Items]
Debt outstanding		721,500,000
Secured debt \| Secured senior term loans due June 30, 2024 ("2024 Term Loans") \| Interest Rate Swap
Debt Instrument [Line Items]
Debt outstanding		$ 350,000,000
Effective interest rate percentage		4.67%
Debt, Weighted Average Interest Rate		2.92%
Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Revolving credit facility maximum borrowing capacity		$ 400,000,000
Line of credit outstanding balances		0	$ 0
Available to borrow and outstanding letters of credit		288,500,000
Outstanding letters of credit		$ 111,500,000