GOODWILL AND OTHER INTANGIBLE ASSETS

12 Months Ended

Dec. 31, 2024

Goodwill and Intangible Assets Disclosure [Abstract]

The changes in goodwill for the years ended December 31, 2024 and 2023 were as follows (in thousands):


	Environmental Services		Safety-Kleen Sustainability Solutions		Total
Balance at January 1, 2023	$	1,071,846	$	175,032	$	1,246,878
Increase from current period acquisitions	39,346		—		39,346
Measurement period adjustments from prior period acquisition	—		360		360


Foreign currency translation	821		331		1,152
Balance at December 31, 2023	$	1,112,013	$	175,723	$	1,287,736
Increase from current period acquisitions	186,911		6,457		193,368
Measurement period adjustments from prior period acquisitions	218		—		218

Foreign currency translation	(2,938)		(1,185)		(4,123)
Balance at December 31, 2024	$	1,296,204	$	180,995	$	1,477,199

The Company assesses goodwill for impairment on an annual basis as of December 31 or at an interim date when it is more likely than not that events or changes in the business environment (“triggering events”) would reduce the fair value of a reporting unit below its carrying value. The Company did not identify any triggering events in the years presented.

Goodwill is also tested for impairment annually. The Company conducted its annual impairment test of goodwill as of December 31, 2024 and determined that no adjustment to the carrying value of goodwill for any reporting unit was then necessary because the fair values of the reporting units exceeded their respective carrying values. The fair value of all reporting units was determined using an income approach based upon estimates of future discounted cash flows. The resulting estimates of fair value were validated through the consideration of other factors such as the fair value of comparable companies to the reporting units and a reconciliation of the sum of all estimated fair values of the reporting units to the Company’s overall market capitalization. In all cases, the estimated fair values of the reporting units significantly exceeded the respective carrying values.

Significant judgments and unobservable inputs, categorized as Level 3 in the fair value hierarchy, are inherent in the impairment tests performed and include assumptions about the amount and timing of expected future cash flows, growth rates, and the determination of appropriate discount rates. Level 3 inputs are unobservable inputs for the asset or liability in which there is little, if any, market activity for the asset or liability at the measurement date. The Company believes that the assumptions used in its impairment tests are reasonable, but variations in any of the assumptions may result in different measurements of fair values.

The impacts of any adverse business and market conditions which may impact the overall performance of the Company's reporting units will continue to be monitored. If the Company's reporting units do not achieve the financial performance that the Company expects, or if there is a significant prolonged change in demand for the Company's products and services, it is possible that goodwill impairment charges may result. Therefore, there can be no assurance that future events will not result in an impairment of goodwill.

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


	December 31, 2024						December 31, 2023
	Cost		Accumulated Amortization		Net		Cost		Accumulated Amortization		Net
Permits	$	191,921	$	123,939	$	67,982	$	191,747	$	117,556	$	74,191
Customer and supplier relationships	697,326		256,657		440,669		604,994		258,879		346,115
Other intangible assets	120,316		46,490		73,826		100,068		37,862		62,206
Total amortizable permits and other intangible assets	1,009,563		427,086		582,477		896,809		414,297		482,512
Trademarks and trade names	119,510		—		119,510		120,285		—		120,285
Total permits and other intangible assets	$	1,129,073	$	427,086	$	701,987	$	1,017,094	$	414,297	$	602,797

During the periods presented, there were no events or changes in circumstances which would indicate that the carrying values of the Company's asset groups would not be recoverable and thus no impairment charges were recorded. If expectations of future cash flows were to decrease in the future as a result of worse than expected or prolonged periods of depressed activity, future impairments may become evident.

Amortization expense of permits, customer and supplier relationships and other intangible assets for the years ended December 31, 2024, 2023 and 2022 were $54.4 million, $50.3 million and $50.2 million, respectively.

The expected amortization of the net carrying amount of finite-lived intangible assets at December 31, 2024 was as follows (in thousands):


Years ending December 31,	Expected Amortization
2025	$	53,335
2026	51,297
2027	49,221
2028	47,916
2029	46,763
Thereafter	333,945
	$	582,477