REVENUES (Tables)

3 Months Ended

Mar. 31, 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 March 31, 2024
	Environmental Services		Safety-Kleen Sustainability Solutions		Corporate		Total
Primary Geographical Markets
United States	$	1,053,458	$	193,912	$	102	$	1,247,472
Canada	107,821		21,402		—		129,223
Total third-party revenues	$	1,161,279	$	215,314	$	102	$	1,376,695
Sources of Revenue
Technical Services	$	407,491	$	—	$	—	$	407,491
Industrial Services and Other	359,397		—		102		359,499
Field and Emergency Response Services	163,469		—		—		163,469
Safety-Kleen Environmental Services	230,922		53,021		—		283,943
Safety-Kleen Oil	—		162,293		—		162,293
Total third-party revenues	$	1,161,279	$	215,314	$	102	$	1,376,695

	Three Months Ended March 31, 2023
	Environmental Services		Safety-Kleen Sustainability Solutions		Corporate		Total
Primary Geographical Markets
United States	$	958,584	$	221,771	$	107	$	1,180,462
Canada	102,398		24,527		—		126,925
Total third-party revenues	$	1,060,982	$	246,298	$	107	$	1,307,387
Sources of Revenue
Technical Services	$	366,509	$	—	$	—	$	366,509
Industrial Services and Other	336,379		—		107		336,486
Field and Emergency Response Services	148,086		—		—		148,086
Safety-Kleen Environmental Services	210,008		49,559		—		259,567
Safety-Kleen Oil	—		196,739		—		196,739
Total third-party revenues	$	1,060,982	$	246,298	$	107	$	1,307,387

Schedule of Contract Balances

(in thousands)	March 31, 2024		December 31, 2023
Receivables	$	1,039,763	$	983,111
Contract assets (unbilled receivables)	165,592		107,859
Contract liabilities (deferred revenue)	106,425		95,230