REVENUES (Tables)

9 Months Ended

Sep. 30, 2024

Revenue from Contract with Customer [Abstract]

Schedule of Disaggregation of Revenue

The following tables present the Company's third-party revenue disaggregated by source of revenue and geography (in thousands):

	Three Months Ended September 30, 2024
	Environmental Services		Safety-Kleen Sustainability Solutions		Corporate		Total
Primary Geographical Markets
United States	$	1,166,660	$	218,963	$	96	$	1,385,719
Canada	120,990		22,713		—		143,703
Total third-party revenues	$	1,287,650	$	241,676	$	96	$	1,529,422
Sources of Revenue
Technical Services	$	437,180	$	—	$	—	$	437,180
Industrial Services and Other	345,573		—		96		345,669
Field and Emergency Response Services	260,200		—		—		260,200
Safety-Kleen Environmental Services	244,697		59,675		—		304,372
Safety-Kleen Oil	—		182,001		—		182,001
Total third-party revenues	$	1,287,650	$	241,676	$	96	$	1,529,422

	Three Months Ended September 30, 2023
	Environmental Services		Safety-Kleen Sustainability Solutions		Corporate		Total
Primary Geographical Markets
United States	$	1,017,224	$	206,860	$	112	$	1,224,196
Canada	118,055		23,445		—		141,500
Total third-party revenues	$	1,135,279	$	230,305	$	112	$	1,365,696
Sources of Revenue
Technical Services	$	403,889	$	—	$	—	$	403,889
Industrial Services and Other	350,251		—		112		350,363
Field and Emergency Response Services	155,046		—		—		155,046
Safety-Kleen Environmental Services	226,093		59,458		—		285,551
Safety-Kleen Oil	—		170,847		—		170,847
Total third-party revenues	$	1,135,279	$	230,305	$	112	$	1,365,696

	Nine Months Ended September 30, 2024
	Environmental Services		Safety-Kleen Sustainability Solutions		Corporate		Total
Primary Geographical Markets
United States	$	3,395,446	$	645,664	$	297	$	4,041,407
Canada	350,781		66,648		—		417,429
Total third-party revenues	$	3,746,227	$	712,312	$	297	$	4,458,836
Sources of Revenue
Technical Services	$	1,288,339	$	—	$	—	$	1,288,339
Industrial Services and Other	1,064,441		—		297		1,064,738
Field and Emergency Response Services	676,562		—		—		676,562
Safety-Kleen Environmental Services	716,885		171,117		—		888,002
Safety-Kleen Oil	—		541,195		—		541,195
Total third-party revenues	$	3,746,227	$	712,312	$	297	$	4,458,836

	Nine Months Ended September 30, 2023
	Environmental Services		Safety-Kleen Sustainability Solutions		Corporate		Total
Primary Geographical Markets
United States	$	3,017,547	$	641,625	$	335	$	3,659,507
Canada	340,196		71,280		—		411,476
Total third-party revenues	$	3,357,743	$	712,905	$	335	$	4,070,983
Sources of Revenue
Technical Services	$	1,160,306	$	—	$	—	$	1,160,306
Industrial Services and Other	1,086,175		—		335		1,086,510
Field and Emergency Response Services	457,491		—		—		457,491
Safety-Kleen Environmental Services	653,771		171,469		—		825,240
Safety-Kleen Oil	—		541,436		—		541,436
Total third-party revenues	$	3,357,743	$	712,905	$	335	$	4,070,983

Schedule of Contract Balances

(in thousands)	September 30, 2024		December 31, 2023
Receivables	$	1,100,660	$	983,111
Contract assets (unbilled receivables)	204,308		107,859
Contract liabilities (deferred revenue)	103,291		95,230