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Commitments and Contingencies - Additional Information (Detail) $ in Thousands | 1 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Nov. 30, 2011 USD ($) | Sep. 30, 2011 USD ($) | Sep. 30, 2015 USD ($) a | Apr. 30, 2011 USD ($) | May. 31, 2009 USD ($)
Greenwood Street Landfill [Member] |  |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |  |
Future remediation costs |  |  | $ 129 |  |
Greenwood Street Landfill [Member] | Administrative Penalty [Member] |  |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |  |
Future remediation costs |  |  | $ 172 |  |
Potsdam Environmental Remediation Liability [Member] |  |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |  |
Scrap yard and solid waste transfer station | a |  |  | 25 |  |
Estimate of total undiscounted costs associated with implementing the preferred remedies |  |  |  | $ 12,130 | $ 10,219
Risk free interest rate |  |  | 1.70% |  |
Potsdam Environmental Remediation Liability [Member] | Motors Liquidation Trust - DEC [Member] |  |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |  |
Future remediation costs |  | $ 3,000 |  |  |
Potsdam Environmental Remediation Liability [Member] | Motors Liquidation Trust - Casella Waste Systems, Inc [Member] |  |  |  |  |
Contingencies And Commitments [Line Items] |  |  |  |  |
Future remediation costs | $ 100 |  |  |  |

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