Condensed Consolidated Statements Of Comprehensive Income (Unaudited) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income (loss) attributable to TechnipFMC plc		$ (167.0)	$ 11.7	$ 201.2	$ (3,244.4)
Income from continuing operations attributable to non-controlling interests		(2.1)	(1.8)	(3.9)	(8.7)
Income from discontinued operations attributable to non-controlling interests		0.0	(1.8)	(1.9)	(5.3)
Net income (loss)		(164.9)	15.3	207.0	(3,230.4)
Foreign currency translation adjustments
Foreign currency translation adjustments	[1]	83.5	15.1	55.4	(202.8)
Net losses on hedging instruments
Net (gains) losses arising during the period		2.5	34.0	(12.0)	(55.3)
Reclassification adjustment for net (gains) losses included in net income		4.7	4.7	2.0	4.8
Net losses on hedging instruments	[2]	7.2	38.7	(10.0)	(50.5)
Pension and other post-retirement benefits
Net gains (losses) arising during the period		(2.3)	2.9	1.2	2.2
Reclassification adjustment for amortization of prior service cost included in net loss		0.2	0.2	0.3	0.5
Reclassification adjustment for amortization of net actuarial loss included in net loss		4.8	2.2	9.6	4.4
Net pension and other postretirement benefits	[3]	2.7	5.3	11.1	7.1
Other comprehensive income (loss), net of tax		93.4	59.1	56.5	(246.2)
Comprehensive income (loss)		(71.5)	74.4	263.5	(3,476.6)
Comprehensive (income) loss attributable to non-controlling interest		(1.9)	(6.8)	(5.7)	(6.1)
Comprehensive income (loss) attributable to TechnipFMC plc		$ (73.4)	$ 67.6	$ 257.8	$ (3,482.7)

[1] Net of income tax benefit of nil for the three and six months ended June 30, 2021 and 2020.

[2] Net of income tax (expense) benefit of $(1.9) million and $(6.7) million for the three months ended June 30, 2021 and 2020, respectively, and $3.0 million and $15.8 million for the six months ended June 30, 2021 and 2020, respectively.

[3] Net of income tax (expense) benefit of $(1.3) million and $(0.9) million for the three months ended June 30, 2021 and 2020, respectively, and $(3.4) million and $(1.5) million for the six months ended June 30, 2021 and 2020, respectively.