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COMMITMENTS AND CONTINGENCIES - Additional Information (Detail) |  | 12 Months Ended |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Apr. 28, 2017 USD ($) | Dec. 31, 2018 USD ($) | Mar. 31, 2018 USD ($) | Apr. 26, 2017 USD ($) | Mar. 31, 2017 USD ($) | Jan. 29, 2016 | Apr. 30, 2011 USD ($) | May 31, 2009 USD ($) | Dec. 20, 2000 a
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Reserve for probable loss |  |  | $ 1,216,000 |  | $ 0 |  |  |  |
Southbridge Landfill |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Risk free interest percentage rate |  |  | 2.60% |  |  |  |  |  |
Reserve for probable loss |  |  | $ 1,216 |  |  |  |  |  |
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 |  |  |  |  |  |  |  |
Maximum | Southbridge Landfill | Scenario, Forecast |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |
Future cash payments |  | $ 2,199,000 |  |  |  |  |  |  |
Maximum | 21E Settlement and Water System Construction Funding Agreement | Bonds |  |  |  |  |  |  |  |  |
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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