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, 2024	Mar. 31, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share
Net income attributable to TechnipFMC plc	$ 157.1	$ 0.4
Weighted Average Number of Shares Outstanding, Diluted, Adjustment [Abstract]
Weighted average number of shares outstanding (in shares)	433.6	442.1
Total shares and dilutive securities (in shares)	446.3	455.0
Earnings per share attributable to TechnipFMC plc
Basic (usd per share)	$ 0.36	$ 0.00
Diluted (usd per share)	$ 0.35	$ 0.00
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0.9	2.6
Share option awards
Earnings per share attributable to TechnipFMC plc
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0.5	1.4
Restricted share units
Earnings per share attributable to TechnipFMC plc
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0.0	0.7
Performance shares
Earnings per share attributable to TechnipFMC plc
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0.4	0.5
Restricted share units
Weighted Average Number of Shares Outstanding, Diluted, Adjustment [Abstract]
Dilutive effect of restricted stock units (in shares)	5.0	7.0
Share option awards
Weighted Average Number of Shares Outstanding, Diluted, Adjustment [Abstract]
Dilutive effect of restricted stock units (in shares)	0.1	0.0
Performance shares
Weighted Average Number of Shares Outstanding, Diluted, Adjustment [Abstract]
Dilutive effect of restricted stock units (in shares)	7.6	5.9