SEGMENT REPORTING - Summary of Revenue Attributable to Services Provided by Company (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue from External Customer [Line Items]
Revenues	$ 193,619	$ 198,547	$ 187,459	$ 163,664	$ 174,724	$ 172,832	$ 165,649	$ 147,455	$ 743,290	$ 660,660	$ 599,309
Revenues percentage									100.00%	100.00%	100.00%
Collection
Revenue from External Customer [Line Items]
Revenues									$ 372,041	$ 303,418	$ 263,688
Revenues percentage									50.10%	45.90%	44.00%
Disposal
Revenue from External Customer [Line Items]
Revenues									$ 181,895	$ 181,110	$ 160,073
Revenues percentage									24.50%	27.40%	26.70%
Power generation
Revenue from External Customer [Line Items]
Revenues									$ 3,576	$ 5,129	$ 5,375
Revenues percentage									0.50%	0.80%	0.90%
Processing
Revenue from External Customer [Line Items]
Revenues									$ 7,175	$ 7,174	$ 7,994
Revenues percentage									0.90%	1.10%	1.30%
Solid waste operations
Revenue from External Customer [Line Items]
Revenues									$ 564,687	$ 496,831	$ 437,130
Revenues percentage									76.00%	75.20%	72.90%
Organics
Revenue from External Customer [Line Items]
Revenues									$ 56,326	$ 54,174	$ 39,815
Revenues percentage									7.50%	8.20%	6.60%
Customer solutions
Revenue from External Customer [Line Items]
Revenues									$ 79,457	$ 67,464	$ 60,057
Revenues percentage									10.70%	10.20%	10.10%
Recycling
Revenue from External Customer [Line Items]
Revenues									$ 42,820	$ 42,191	$ 62,307
Revenues percentage									5.80%	6.40%	10.40%