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BUSINESS COMBINATIONS - Narrative (Detail) - transfer_station	12 Months Ended
	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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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The number of businesses acquired by the entity during the period.

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