Impairment, Restructuring and Other Exit Costs - Schedule of Impairment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Restructuring [Line Items]
Goodwill impairment	$ 169,000
Total impairment expense	297,604	$ 292,551
Diversified Services
Restructuring [Line Items]
Goodwill impairment	168,568	2,125
Stork Holding B.V.
Restructuring [Line Items]
Intangible customer relationships associated with the Stork business	26,671	33,657
Energy & Chemicals
Restructuring [Line Items]
Equity Method Investment, Other than Temporary Impairment	86,096	256,769
Technology-Based Intangible Assets
Restructuring [Line Items]
Impairment loss on intangible assets	$ 16,269	$ 0

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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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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