Merger of FMC Technologies and Technip (Pro Forma Impact) (Details) - FMCTI Merger - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Business Acquisition
Revenue	$ 4,140.9	$ 3,454.8	$ 11,486.8	$ 10,587.2
Net income attributable to TechnipFMC adjusted for dilutive effects	$ 121.0	$ 306.9	$ 182.4	$ 436.1
Diluted earnings per share (usd per share)	$ 0.26	$ 0.65	$ 0.39	$ 0.93

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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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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