Business Combination Transactions (Pro Forma Impact) (Details) - FMCTI Merger - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Business Acquisition [Line Items]
Revenue	$ 15,169.8	$ 13,727.9
Net income attributable to TechnipFMC adjusted for dilutive effects	$ 28.5	$ 291.8
Diluted earnings per share (usd per share)	$ 0.06	$ 0.62

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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 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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