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BUSINESS COMBINATIONS - Narrative (Detail) | 12 Months Ended
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Dec. 31, 2019 vote transfer_station | Dec. 31, 2018 transfer_station vote | Dec. 31, 2017 transfer_station
Business Acquisition [Line Items] |  |  |
Number of businesses acquired | 9 | 9 | 4
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 |  |
Eastern | Solid Waste Collection Business |  |  |
Business Acquisition [Line Items] |  |  |
Number of businesses acquired | 3 |  | 1
Eastern | Collection Business |  |  |
Business Acquisition [Line Items] |  |  |
Number of businesses acquired |  | 2 |
Western | Solid Waste Collection Business |  |  |
Business Acquisition [Line Items] |  |  |
Number of businesses acquired | 4 | 6 | 3
Western | Transfer Business |  |  |
Business Acquisition [Line Items] |  |  |
Number of businesses acquired |  | 1 |

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