REVENUES (Tables)

6 Months Ended

Jun. 30, 2022

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):

	For the Three Months Ended June 30, 2022
	Environmental Services		Safety-Kleen Sustainability Solutions		Corporate		Total
Primary Geographical Markets
United States	$	945,579	$	236,879	$	79	$	1,182,537
Canada	138,927		34,848		—		173,775
Total third-party revenues	$	1,084,506	$	271,727	$	79	$	1,356,312
Sources of Revenue
Technical Services	$	387,019	$	—	$	—	$	387,019
Field and Emergency Response Services (1)	144,860		—		—		144,860
Industrial Services and Other (2)	360,870		—		79		360,949
Safety-Kleen Environmental Services	191,757		49,381		—		241,138
Safety-Kleen Oil	—		222,346		—		222,346
Total third-party revenues	$	1,084,506	$	271,727	$	79	$	1,356,312

_____________

(1) Includes approximately $34.2 million of third-party revenues from the operations of the HydroChemPSC business

(2) Includes approximately $173.7 million of third-party revenues from the operations of the HydroChemPSC business

	For the Three Months Ended June 30, 2021
	Environmental Services		Safety-Kleen Sustainability Solutions		Corporate		Total
Primary Geographical Markets
United States	$	616,585	$	180,216	$	79	$	796,880
Canada	106,562		23,016		—		129,578
Total third-party revenues	$	723,147	$	203,232	$	79	$	926,458
Sources of Revenue
Technical Services	$	306,865	$	—	$	—	$	306,865
Field and Emergency Response Services	106,986		—		—		106,986
Industrial Services and Other	150,367		—		79		150,446
Safety-Kleen Environmental Services	158,929		40,453		—		199,382
Safety-Kleen Oil	—		162,779		—		162,779
Total third-party revenues	$	723,147	$	203,232	$	79	$	926,458

	For the Six Months Ended June 30, 2022
	Environmental Services		Safety-Kleen Sustainability Solutions		Corporate		Total
Primary Geographical Markets
United States	$	1,780,257	$	439,409	$	151	$	2,219,817
Canada	245,047		60,557		—		305,604
Total third-party revenues	$	2,025,304	$	499,966	$	151	$	2,525,421
Sources of Revenue
Technical Services	$	710,675	$	—	$	—	$	710,675
Field and Emergency Response Services (1)	277,219		—		—		277,219
Industrial Services and Other (2)	669,708		—		151		669,859
Safety-Kleen Environmental Services	367,702		93,769		—		461,471
Safety-Kleen Oil	—		406,197		—		406,197
Total third-party revenues	$	2,025,304	$	499,966	$	151	$	2,525,421

_____________

(1) Includes approximately $62.2 million of third-party revenues from the operations of the HydroChemPSC business

(2) Includes approximately $329.8 million of third-party revenues from the operations of the HydroChemPSC business

	For the Six Months Ended June 30, 2021
	Environmental Services		Safety-Kleen Sustainability Solutions		Corporate		Total
Primary Geographical Markets
United States	$	1,192,093	$	319,206	$	158	$	1,511,457
Canada	183,932		39,217		—		223,149
Total third-party revenues	$	1,376,025	$	358,423	$	158	$	1,734,606
Sources of Revenue
Technical Services	$	578,905	$	—	$	—	$	578,905
Field and Emergency Response Services	212,154		—		—		212,154
Industrial Services and Other	270,177		—		158		270,335
Safety-Kleen Environmental Services	314,789		79,431		—		394,220
Safety-Kleen Oil	—		278,992		—		278,992
Total third-party revenues	$	1,376,025	$	358,423	$	158	$	1,734,606

Schedule of Contract Balances

(in thousands)	June 30, 2022		December 31, 2021
Receivables	$	1,005,488	$	792,734
Contract assets (unbilled receivables)	134,173		94,963
Contract liabilities (deferred revenue)	94,531		83,749