GOODWILL AND OTHER INTANGIBLE ASSETS - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Intangible Assets By Major Class [Line Items]
Aggregate intangible asset amortization expense	$ 31.8	$ 29.9	$ 96.6	$ 88.5	$ 118.4
Domestic And Canada Regulated Waste And Compliance Services
Intangible Assets By Major Class [Line Items]
Aggregate intangible asset amortization expense	23.7	22.0	71.1	65.6
International Regulated Waste And Compliance Services
Intangible Assets By Major Class [Line Items]
Aggregate intangible asset amortization expense	6.0	$ 5.9	19.2	$ 16.8
International Regulated Waste And Compliance Services | Operating permits
Intangible Assets By Major Class [Line Items]
Indefinite-lived assets impairment charges	0.0		$ 1.2
Customer relationships
Intangible Assets By Major Class [Line Items]
Finite-lived intangible assets, weighted average remaining useful life			11 years
Customer relationships | Minimum
Intangible Assets By Major Class [Line Items]
Finite-lived intangible assets, useful life			10 years
Customer relationships | Maximum
Intangible Assets By Major Class [Line Items]
Finite-lived intangible assets, useful life			30 years
Customer relationships | Domestic And Canada Regulated Waste And Compliance Services
Intangible Assets By Major Class [Line Items]
Reclassification of intangibles to assets held for sale	14.4		$ 14.4
Definite-lived assets non-cash impairment / Customer relationship intangibles	0.5
Customer relationships | International Regulated Waste And Compliance Services
Intangible Assets By Major Class [Line Items]
Definite-lived assets non-cash impairment / Customer relationship intangibles	0.0		$ 3.0
Tradenames
Intangible Assets By Major Class [Line Items]
Finite-lived intangible assets, weighted average remaining useful life			17 years 8 months 12 days
Tradenames | Minimum
Intangible Assets By Major Class [Line Items]
Finite-lived intangible assets, useful life			4 years
Tradenames | Maximum
Intangible Assets By Major Class [Line Items]
Finite-lived intangible assets, useful life			40 years
Tradenames | International Regulated Waste And Compliance Services
Intangible Assets By Major Class [Line Items]
Indefinite-lived assets impairment charges	$ 0.0		$ 1.0
Covenants not-to-compete
Intangible Assets By Major Class [Line Items]
Finite-lived intangible assets, weighted average remaining useful life			2 years 2 months 12 days
Covenants not-to-compete | Minimum
Intangible Assets By Major Class [Line Items]
Finite-lived intangible assets, useful life			5 years
Covenants not-to-compete | Maximum
Intangible Assets By Major Class [Line Items]
Finite-lived intangible assets, useful life			14 years
Other intangibles
Intangible Assets By Major Class [Line Items]
Finite-lived intangible assets, weighted average remaining useful life			16 years