Acquisitions and Dispositions - Pro Forma Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Gain on Sale from discontinued business	$ (569,135)
Clean Earth
Business Acquisition [Line Items]
Business Acquisition, Pro Forma Revenue	1,635,900	$ 1,614,600
Business Acquisition, Pro Forma Net Income (Loss)	517,600	$ 116,100
Gain on Sale from discontinued business	$ 453,600

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.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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