Earnings Per Share (Reconciliation Of Number Of Shares Used For Basic And Diluted Earnings Per Share ("EPS") Calculation ) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share
Net income attributable to TechnipFMC plc	$ 190.8	$ 147.4
After-tax interest expense related to dilutive shares		3.2
Net income attributable to TechnipFMC plc adjusted for dilutive effects	$ 190.8	$ 150.6
Weighted average number of shares outstanding (in shares)	466.6	118.2
Total shares and dilutive securities (in shares)	468.9	124.4
Basic earnings per share attributable to TechnipFMC plc (usd per share)	$ 0.41	$ 1.25
Diluted earnings per share attributable to technipFMC plc (usd per share)	$ 0.41	$ 1.21
Employee Stock Option
Antidilutive Securities Excluded from Computation of Earnings Per Share
Dilutive effect of share-based payment arrangements (in shares)	0.5
Performance Shares
Antidilutive Securities Excluded from Computation of Earnings Per Share
Dilutive effect of share-based payment arrangements (in shares)	1.8	1.0
Convertible Debt Securities
Antidilutive Securities Excluded from Computation of Earnings Per Share
Dilutive effect of convertible bonds (in shares)		5.2

Interest Expense Related to Dilutive Shares, Net of Tax

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount after tax of income (loss) from continuing operations attributable to the parent.

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