Operating Information by Segment and Geographic Area - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Segment reporting information
Revenue	$ 2,938,526	$ 3,697,694
Capital contributions by NCI	42,101	19,968
Energy Solutions
Segment reporting information
Expense from embedded foreign currency derivatives	29,000
Equity method investments	26,392	86,096
Energy Solutions \| Credit Losses Associated with Clients Affected by Impacts of COVID-19
Segment reporting information
Impact of the recognition of reserves		55,000
Urban Solutions \| Reportable segments
Segment reporting information
Revenue	69,000	77,000
Other \| Nu Scale Power \| Reportable segments
Segment reporting information
Qualified expenses reimbursed	15,000	$ 13,000
Other \| Nu Scale Power \| JGC Holdings Corporation \| Reportable segments
Segment reporting information
Capital contributions by NCI	$ 40,000

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