Merger of FMC Technologies and Technip (Acquisition Date Fair Value) (Details) $ / shares in Units, shares in Millions, $ in Millions	Jan. 16, 2017 USD ($) $ / shares shares	Mar. 31, 2018 shares	Dec. 31, 2017 shares
Business Acquisition
Shares subject to exchange (in shares)		462.2	465.1
Euro to U.S. dollar exchange rate	1.0594
Technip
Business Acquisition
FMC Technologies Inc. exchange ratio(a)	2.0
FMCTI Merger
Business Acquisition
Shares subject to exchange (in shares)	228.9
FMC Technologies Inc. exchange ratio(a)	0.5
Shares of TechnipFMC issued (in shares)	114.4
Value per share of Technip (usd per share) | $ / shares	$ 71.40
Total purchase consideration | $	$ 8,170.7