GOODWILL AND OTHER INTANGIBLE ASSETS (Tables)

9 Months Ended

Sep. 30, 2024

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Changes to Goodwill

The changes in goodwill by segment for the nine months ended September 30, 2024 were as follows (in thousands):

	Environmental Services		Safety-Kleen Sustainability Solutions		Totals
Balance at January 1, 2024	$	1,112,013	$	175,723	$	1,287,736
Increase from current period acquisitions	194,845		3,311		198,156
Measurement period adjustments from prior period acquisitions	218		—		218
Foreign currency translation	(745)		(300)		(1,045)
Balance at September 30, 2024	$	1,306,331	$	178,734	$	1,485,065

Schedule of Finite-Lived Intangible Assets

As of September 30, 2024 and December 31, 2023, the Company’s intangible assets consisted of the following (in thousands):

	September 30, 2024						December 31, 2023
	Cost		Accumulated Amortization		Net		Cost		Accumulated Amortization		Net
Permits	$	193,201	$	123,335	$	69,866	$	191,747	$	117,556	$	74,191
Customer and supplier relationships	697,295		249,215		448,080		604,994		258,879		346,115
Other intangible assets	114,112		43,210		70,902		100,068		37,862		62,206
Total amortizable permits and other intangible assets	1,004,608		415,760		588,848		896,809		414,297		482,512
Trademarks and trade names	120,087		—		120,087		120,285		—		120,285
Total permits and other intangible assets	$	1,124,695	$	415,760	$	708,935	$	1,017,094	$	414,297	$	602,797

Summary of Indefinite-Lived Intangible Assets

As of September 30, 2024 and December 31, 2023, the Company’s intangible assets consisted of the following (in thousands):

	September 30, 2024						December 31, 2023
	Cost		Accumulated Amortization		Net		Cost		Accumulated Amortization		Net
Permits	$	193,201	$	123,335	$	69,866	$	191,747	$	117,556	$	74,191
Customer and supplier relationships	697,295		249,215		448,080		604,994		258,879		346,115
Other intangible assets	114,112		43,210		70,902		100,068		37,862		62,206
Total amortizable permits and other intangible assets	1,004,608		415,760		588,848		896,809		414,297		482,512
Trademarks and trade names	120,087		—		120,087		120,285		—		120,285
Total permits and other intangible assets	$	1,124,695	$	415,760	$	708,935	$	1,017,094	$	414,297	$	602,797

Schedule of Expected Amortization for the Net Carrying Amount of Finite Lived Intangible Assets

The expected amortization of the net carrying amount of finite-lived intangible assets at September 30, 2024 was as follows (in thousands):

Years Ending December 31,	Expected Amortization
2024 (three months)	$	13,608
2025	57,103
2026	50,813
2027	48,308
2028	46,836
Thereafter	372,180
	$	588,848