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BUSINESS COMBINATIONS - Narrative (Detail) $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jan. 31, 2018 USD ($) | Dec. 31, 2017 transfer_station | Dec. 31, 2015 transfer_station
Business Acquisition [Line Items] |  |  |
Number of businesses acquired |  |  | 0
Intangible assets, useful life |  | 10 years |
Minimum |  |  |
Business Acquisition [Line Items] |  |  |
Intangible assets, useful life |  | 5 years |
Maximum |  |  |
Business Acquisition [Line Items] |  |  |
Intangible assets, useful life |  | 10 years |
Subsequent Event |  |  |
Business Acquisition [Line Items] |  |  |
Total consideration from Complete Disposal acquisition | $ | $ 16,500 |  |
Eastern | Collection Business |  |  |
Business Acquisition [Line Items] |  |  |
Number of businesses acquired |  | 1 |
Western | Solid Waste Collection Business |  |  |
Business Acquisition [Line Items] |  |  |
Number of businesses acquired |  | 3 |

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