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COMMITMENTS AND CONTINGENCIES - Narrative (Detail) |  | 8 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Apr. 12, 2016 USD ($) | Dec. 31, 2014 USD ($) | Dec. 31, 2016 USD ($) executive_officer | Dec. 31, 2015 USD ($) | Apr. 30, 2014 USD ($) | Jan. 29, 2016 | Apr. 30, 2011 USD ($) | May 31, 2009 USD ($) | Dec. 20, 2000 a
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Monthly payments (up to) |  |  | $ 20,000 |  |  |  |  |  |
Total rent expense under operating leases charged to operations |  | $ 4,868,000 | $ 11,437,000 | $ 9,392,000 | $ 5,651,000 |  |  |  |
Intangible assets, useful life |  |  | 10 years |  |  |  |  |  |
Contract settlement charge |  | $ 0 | $ 0 | 1,940,000 | $ 0 |  |  |  |
Number of executive officers | executive_officer |  |  | 5 |  |  |  |  |  |
Contract extension period |  |  | 1 year |  |  |  |  |  |
Total annual commitments for salaries |  |  | $ 1,646,000 |  |  |  |  |  |
Expera Old Town LLC |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Fuel replacement fee (up to) |  |  | 2,000,000 |  |  |  |  |  |
Intangible assets, useful life | 5 years |  |  |  |  |  |  |  |
Reserve related with settlement |  |  | 1,448,000 | 2,616,000 |  |  |  |  |
Contract settlement charge |  |  |  | 1,940,000 |  |  |  |  |
Southbridge Recycling & Disposal Park, Inc. vs Southbridge, Massachusetts |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Incurred total costs to date |  |  | 2,465,000 |  |  |  |  |  |
Notice of Intent to Sue under the Resource Conservation and Recovery Act |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Agreement in principle amount (up to) |  |  | $ 5,000,000 |  |  |  |  |  |
Upon execution of SA | Expera Old Town LLC |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Litigation settlement | $ 1,250,000 |  |  |  |  |  |  |  |
Five years following execution of SA | Expera Old Town LLC |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Litigation settlement | $ 350,000 |  |  |  |  |  |  |  |
Operating Expense | Expera Old Town LLC |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Reserve related with settlement |  |  |  | $ 676,000 |  |  |  |  |
Maximum |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Intangible assets, useful life |  |  | 10 years |  |  |  |  |  |
Initial term of employment contract |  |  | 3 years |  |  |  |  |  |
Salary and bonuses payment range |  |  | 3 years |  |  |  |  |  |
Maximum | Employment Contracts |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Intangible assets, useful life |  |  | 2 years |  |  |  |  |  |
Minimum |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Intangible assets, useful life |  |  | 5 years |  |  |  |  |  |
Initial term of employment contract |  |  | 1 year |  |  |  |  |  |
Salary and bonuses payment range |  |  | 1 year |  |  |  |  |  |
Minimum | Employment Contracts |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Intangible assets, useful life |  |  | 1 year |  |  |  |  |  |
Potsdam Environmental Remediation Liability |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Number of acres composing solid waste transfer station (in acres) | a |  |  |  |  |  |  |  |  | 25
Estimate of total undiscounted costs associated with implementing the preferred remedies |  |  |  |  |  |  | $ 12,130,000 | $ 10,219,000 |
Remediation activities, participant share percentage |  |  |  |  |  | 15.00% |  |  |
Risk free interest rate |  |  | 1.50% |  |  |  |  |  |
MADEP | Notice of Intent to Sue under the Resource Conservation and Recovery Act |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Agreement in principle amount (up to) |  |  | $ 5,000,000 |  |  |  |  |  |
Massachusetts Department of Environmental Protection (MADEP) and Casella Waste Systems | Notice of Intent to Sue under the Resource Conservation and Recovery Act |  |  |  |  |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |  |  |  |  |
Agreement in principle amount (up to) |  |  | $ 10,000,000 |  |  |  |  |  |

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