EARNINGS (LOSS) 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	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Income (loss) from continuing operations attributable to TechnipFMC plc	$ 56.2	$ (61.9)	$ 87.8
Loss from discontinued operations attributable to TechnipFMC plc	0.0	(45.3)	(74.5)
Net income (loss) attributable to TechnipFMC plc	$ 56.2	$ (107.2)	$ 13.3
Weighted average number of shares outstanding (in shares)	438.6	449.5	450.5
Total shares and dilutive securities (in shares)	452.3	449.5	454.6
Earnings (loss) per share from continuing operations attributable to TechnipFMC plc Basic (usd per share)	$ 0.13	$ (0.14)	$ 0.19
Earnings (loss) per share from continuing operations attributable to TechnipFMC plc Diluted (usd per share)	0.12	(0.14)	0.19
Earnings (loss) per share from discontinued operations attributable to TechnipFMC plc Basic (usd per share)	0	(0.10)	(0.17)
Earnings (loss) per share from discontinued operations attributable to TechnipFMC plc Diluted (usd per share)	0	(0.10)	(0.16)
Total earnings (loss) per share attributable to TechnipFMC plc Basic (usd per share)	0.13	(0.24)	0.03
Total earnings (loss) per share attributable to TechnipFMC plc Diluted (usd per share)	$ 0.12	$ (0.24)	$ 0.03
Incremental shares from share-based compensation excluded due to being anti-dilutive (shares)		8.9
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0.8	1.5	1.8
Share option awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0.8	1.5	1.7
Restricted share units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0.0	0.0	0.1
Restricted share units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive effect of restricted stock units (in shares)	5.7	0.0	4.1
Performance shares
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Dilutive effect of restricted stock units (in shares)	8.0		0.0