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BUSINESS COMBINATIONS - Narrative (Detail) - transfer_station | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Business Acquisition [Line Items] |  |
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 |
Western | Solid Waste Collection Business |  |
Business Acquisition [Line Items] |  |
Number of businesses acquired | 6 | 3
Western | Transfer Business |  |
Business Acquisition [Line Items] |  |
Number of businesses acquired | 1 |
Eastern | Solid Waste Collection Business |  |
Business Acquisition [Line Items] |  |
Number of businesses acquired |  | 1
Eastern | Collection Business |  |
Business Acquisition [Line Items] |  |
Number of businesses acquired | 2 |

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