Percentage participation in onsite remediation activities.

No definition available.

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- Definition

Acreage of scrap yard owned by WSI.

+ References

No definition available.

+ Details

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- Definition

Estimated undiscounted remediation costs.

+ References

No definition available.

+ Details

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 30
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.Y.Q1)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

+ Details

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.Y.Q4)
-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

+ Details

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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.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14557-108349

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- Details

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- Details

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- Details

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COMMITMENTS AND CONTINGENCIES - Additional Information (Detail)	Apr. 28, 2017 USD ($)	Mar. 31, 2019	Apr. 26, 2017 USD ($)	Jan. 29, 2016	Apr. 30, 2011 USD ($)	May 31, 2009 USD ($)	Dec. 20, 2000 a
Southbridge Landfill
Loss Contingencies [Line Items]
Risk free interest percentage rate		2.60%
Potsdam Environmental Remediation Liability
Loss Contingencies [Line Items]
Risk free interest percentage rate		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]
Amount of costs	$ 5,000,000
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 System
Loss Contingencies [Line Items]
Estimate of possible loss			$ 10,000,000