BUSINESS COMBINATIONS - Additional Information (Details) - transfer_station	3 Months Ended	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2017
Eastern | Collection Business
Business Acquisition [Line Items]
Number of transfer stations acquired		1
Western | Solid Waste Collection
Business Acquisition [Line Items]
Number of transfer stations acquired		1
Western | Transfer Stations Acquisition
Business Acquisition [Line Items]
Number of transfer stations acquired	3