Operating Information by Segment and Geographic Area - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Segment reporting information
Revenue	$ 3,122	$ 3,347
Capital contributions by NCI	0	42
Energy Solutions
Segment reporting information
Expense from embedded foreign currency derivatives	13	29
Urban Solutions \| Reportable segments
Segment reporting information
Revenue	$ 60	$ 69

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details