SIGNIFICANT ACCOUNTING POLICIES - Revenue Recognition (Details)	Dec. 31, 2021 source
Environmental Services
Disaggregation of Revenue [Line Items]
Number of revenue sources	4
Safety-Kleen Sustainability Solutions
Disaggregation of Revenue [Line Items]
Number of revenue sources	2

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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