Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Name:	us-gaap_GoodwillImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

GOODWILL AND OTHER INTANGIBLE ASSETS - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) reportingUnit	Sep. 30, 2020 USD ($)
Goodwill [Line Items]
Number of reporting units \| reportingUnit			3
Goodwill impairment \| $			$ 0
Amortization of permits and other intangible assets \| $	$ 7,600,000	$ 9,600,000	22,900,000	$ 27,600,000
Intangible assets, written-off \| $			$ 39,700,000
Environmental Services
Goodwill [Line Items]
Number of reporting units \| reportingUnit			2
Safety-Kleen Sustainability Solutions
Goodwill [Line Items]
Number of reporting units \| reportingUnit			1