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BUSINESS COMBINATIONS - Additional Information (Details) - transfer_station	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Eastern | Solid Waste Collection
Business Acquisition [Line Items]
Number of transfer stations acquired	1
Western | Solid Waste Collection
Business Acquisition [Line Items]
Number of transfer stations acquired	2
Western | Transfer Stations Acquisition
Business Acquisition [Line Items]
Number of transfer stations acquired		3

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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

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- Details

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- Details

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