Percentage participation in onsite remediation activities.

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- Definition

Acreage of scrap yard owned by WSI.

+ References

No definition available.

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- Definition

Estimated undiscounted remediation costs.

+ References

No definition available.

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- Definition

Rate applied to the undiscounted amount of environmental loss contingencies to arrive at the present value recorded as of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- 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.

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- Definition

Total anticipated costs associated with remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal, or abandonment of a particular property resulting from unanticipated contamination of the assets.

+ References

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- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

No definition available.

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- 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.

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- Definition

Amount of loss contingency liability.

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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- Definition

Number of plaintiffs that have filed claims pertaining to a loss contingency.

+ References

No definition available.

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COMMITMENTS AND CONTINGENCIES - Narrative (Detail) numberOfPlantiffs in Thousands				3 Months Ended	9 Months Ended
	Sep. 18, 2020 USD ($)	Sep. 17, 2019 numberOfPlantiffs	Apr. 28, 2017 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)	Apr. 26, 2017 USD ($)	Jan. 29, 2016	Apr. 30, 2011 USD ($)	May 31, 2009 USD ($)	Dec. 20, 2000 a
Southbridge Landfill
Loss Contingencies [Line Items]
Loss contingency, settlement awarded				$ 2,000,000	$ 2,000,000
Risk free interest percentage rate				2.60%	2.60%
Potsdam Environmental Remediation
Loss Contingencies [Line Items]
Risk free interest percentage rate				1.50%	1.50%
Scrap yard and solid waste transfer station (in acres) \| a										25
Undiscounted costs preferred remedies								$ 12,130,000	$ 10,219,000
Remediation activities, participant share percentage							15.00%
21E Settlement and Water System Construction Funding Agreement \| Bonds
Loss Contingencies [Line Items]
Bond period			20 years
21E Settlement and Water System Construction Funding Agreement \| Bonds \| Maximum
Loss Contingencies [Line Items]
Anticipated cost			$ 4,089,000
Citizen Groups and the Residents Litigation Case \| Southbridge Landfill
Loss Contingencies [Line Items]
Loss contingency, settlement awarded	$ 2,000,000
Loss contingency accrual				$ 2,000,000	$ 2,000,000
Citizen Groups and the Residents Litigation Case \| The Town \| Southbridge Landfill
Loss Contingencies [Line Items]
Loss contingency, settlement awarded	1,000,000
Citizen Groups and the Residents Litigation Case \| Casella Waste Systems and the Town \| Southbridge Landfill
Loss Contingencies [Line Items]
Loss contingency, settlement awarded	$ 3,000,000
Notice of Intent to Sue under the Resource Conservation and Recovery Act
Loss Contingencies [Line Items]
Estimate of possible loss						$ 5,000,000
Notice of Intent to Sue under the Resource Conservation and Recovery Act \| MADEP and Casella Waste Systems
Loss Contingencies [Line Items]
Estimate of possible loss						$ 10,000,000
Ontario County, New York Class Action Litigation
Loss Contingencies [Line Items]
Number of citizens seeking damages \| numberOfPlantiffs		1