Business Combination Transactions (Pro Forma Impact) (Details) - FMCTI Merger - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2017
Business Acquisition
Revenue	$ 4,140.9	$ 11,486.8
Net income attributable to TechnipFMC adjusted for dilutive effects	$ 121.0	$ 182.4
Diluted earnings per share (usd per share)	$ 0.26	$ 0.39

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The pro forma diluted net income per share for a 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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