REVENUES FROM CONTRACTS WITH CUSTOMERS - Schedule of Revenues Disaggregated by Service, Primary Geographical Regions and Timing of Revenue Recognition (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Revenues	$ 653.5	$ 690.3	$ 2,007.3	$ 2,034.4
North America
Disaggregation of Revenue [Line Items]
Revenues	557.1	584.8	1,695.7	1,697.2
International
Disaggregation of Revenue [Line Items]
Revenues	96.4	105.5	311.6	337.2
Regulated Waste and Compliance Services
Disaggregation of Revenue [Line Items]
Revenues	439.9	447.8	1,335.9	1,348.9
Regulated Waste and Compliance Services | North America
Disaggregation of Revenue [Line Items]
Revenues	368.0	369.7	1,103.1	1,097.5
Regulated Waste and Compliance Services | International
Disaggregation of Revenue [Line Items]
Revenues	71.9	78.1	232.8	251.4
Secure Information Destruction Services
Disaggregation of Revenue [Line Items]
Revenues	213.6	242.5	671.4	685.5
Secure Information Destruction Services | North America
Disaggregation of Revenue [Line Items]
Revenues	189.1	215.1	592.6	599.7
Secure Information Destruction Services | International
Disaggregation of Revenue [Line Items]
Revenues	$ 24.5	$ 27.4	$ 78.8	$ 85.8