Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2020	Oct. 28, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2020
Document Transition Report	false
Entity File Number	001-37983
Entity Registrant Name	TechnipFMC plc
Entity Incorporation, State or Country Code	X0
Entity Tax Identification Number	98-1283037
Entity Address, Address Line One	One St. Paul’s Churchyard
Entity Address, City or Town	London
Entity Address, Country	GB
Entity Address, Postal Zip Code	EC4M 8AP
Country Region	44
City Area Code	203
Local Phone Number	429-3950
Title of 12(b) Security	Ordinary shares, $1.00 par value per share
Trading Symbol	FTI
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		449,408,233
Entity Central Index Key	0001681459
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Amendment Flag	false