GOODWILL AND OTHER INTANGIBLE ASSETS - Changes to Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Goodwill [Roll Forward]
Goodwill, beginning of period	$ 1,287,736	$ 1,246,878
Increase from current period acquisitions	193,368	39,346
Measurement period adjustments from prior period acquisition	218	360
Foreign currency translation	(4,123)	1,152
Goodwill, end of period	1,477,199	1,287,736
Environmental Services
Goodwill [Roll Forward]
Goodwill, beginning of period	1,112,013	1,071,846
Increase from current period acquisitions	186,911	39,346
Measurement period adjustments from prior period acquisition	218	0
Foreign currency translation	(2,938)	821
Goodwill, end of period	1,296,204	1,112,013
Safety-Kleen Sustainability Solutions
Goodwill [Roll Forward]
Goodwill, beginning of period	175,723	175,032
Increase from current period acquisitions	6,457	0
Measurement period adjustments from prior period acquisition	0	360
Foreign currency translation	(1,185)	331
Goodwill, end of period	$ 180,995	$ 175,723