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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Landfill and Lease Accounting (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 USD ($) agreement | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Property, Plant and Equipment [Line Items] |  |  |
Capitalized interest | $ 413 | $ 263 | $ 140
Closure and post-closure costs incurrence period | 30 years |  |
Estimate of inflation rate | 1.60% |  |
Accretion expense | $ 6,436 | 6,227 |
Number of operation and management agreements entered into | agreement | 3 |  |
Closure and Post Closure Costs |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Accretion expense | $ 6,436 | 6,227 | $ 5,556
Surety bond | 205,048 | 220,633 |
Letters of credit | $ 0 | $ 0 |
Discount Rate | Minimum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Asset retirement obligation measurement input | 8.20% |  |
Discount Rate | Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Asset retirement obligation measurement input | 10.20% |  |

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- Definition Closure and Post-Closure Costs Incurrence Period + References No definition available. + Details
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