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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
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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 |  |  |  |

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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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