Debt Instrument, Interest Rate, Annual Increase, Upon Other Event Of Default

No definition available.

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- Definition

Debt Instrument, Interest Rate, Annual Increase, Upon Payment Default

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Variable Rate Adjustment

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Sublimit to the amount of letters of credit allowed under credit agreement.

+ References

No definition available.

+ Details

Name:	cwst_LettersOfCreditSublimit
Namespace Prefix:	cwst_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of additional optional borrowing capacity under the credit facility.

+ References

No definition available.

+ Details

Name:	cwst_LineOfCreditFacilityAdditionalBorrowingCapacity
Namespace Prefix:	cwst_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line of Credit Facility, Fronting Fee Percentage

+ References

No definition available.

+ Details

Name:	cwst_LineOfCreditFacilityFrontingFeePercentage
Namespace Prefix:	cwst_
Data Type:	dtr-types:percentItemType
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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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+ Details

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

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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

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

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- Details

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DEBT - Credit Facility (Details) - USD ($)		3 Months Ended
DEBT - Credit Facility (Details) - USD ($)	Feb. 09, 2023	Mar. 31, 2023
Line of Credit Facility [Line Items]
Additional revolver capacity		$ 125,000,000
Line of Credit
Line of Credit Facility [Line Items]
Facility term		5 years
Remaining capacity		$ 272,267,000
Line of credit drawn		0
Credit Facility
Line of Credit Facility [Line Items]
Interest rate, annual increase upon payment default	2.00%
Interest rate, annual increase upon other event of default	2.00%
Credit Facility \| Minimum \| Variable Rate Component Two
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	0.20%
Credit Facility \| Maximum \| Variable Rate Component Two
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	0.40%
Credit Facility \| SOFR
Line of Credit Facility [Line Items]
Variable rate adjustment	0.10%
Credit Facility \| SOFR \| Variable Rate Component One
Line of Credit Facility [Line Items]
Variable rate adjustment	0.04%
Credit Facility \| SOFR \| Minimum \| Variable Rate Component One
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	1.125%
Credit Facility \| SOFR \| Maximum \| Variable Rate Component One
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)	2.125%
Secured Debt \| Term loan A facility ("Term Loan Facility") due December 2026; bearing interest at term secured overnight financing rate ("Term SOFR") plus 1.135%
Line of Credit Facility [Line Items]
Aggregate principal amount issued		$ 350,000,000
Secured Debt \| Term loan A facility ("Term Loan Facility") due December 2026; bearing interest at term secured overnight financing rate ("Term SOFR") plus 1.135% \| SOFR
Line of Credit Facility [Line Items]
Basis spread on variable rate (as a percent)		1.135%
Line of Credit \| Credit Facility \| Letter of Credit
Line of Credit Facility [Line Items]
Fronting fee	0.25%
Revolving Credit Facility \| Revolving credit facility ("Revolving Credit Facility") due December 2026; bearing interest at Term SOFR plus 1.135% \| Letter of Credit
Line of Credit Facility [Line Items]
Letters of credit sublimit		$ 75,000,000
Revolving Credit Facility \| Revolving credit facility ("Revolving Credit Facility") due December 2026; bearing interest at Term SOFR plus 1.135% \| Line of Credit
Line of Credit Facility [Line Items]
Credit facility maximum		300,000,000
Outstanding irrevocable letters of credit totaling		$ 27,733,000