Condensed Consolidated Statements of Changes In Stockholders' Equity (Unaudited) - USD ($) $ in Millions	Total	Technip Energies	Cumulative Effect, Period of Adoption, Adjustment	Ordinary Shares	Capital in Excess of Par Value of Ordinary Shares	Accumulated Deficit	Accumulated Deficit Cumulative Effect, Period of Adoption, Adjustment	Accumulated Other Comprehensive Income (Loss)	Non-controlling Interest
Beginning balance at Dec. 31, 2019	$ 7,688.1		$ (7.8)	$ 447.1	$ 10,182.8	$ (1,563.1)	$ (7.8)	$ (1,407.5)	$ 28.8
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(3,224.0)					(3,248.3)			24.3
Other comprehensive income (loss)	(208.0)							(201.6)	(6.4)
Issuance of ordinary shares	(5.3)			2.3	(7.6)
Cash dividends declared	(59.2)					(59.2)
Share-based compensation (Note 15)	52.6				52.6
Other	(2.7)					(0.6)			(2.1)
Ending balance at Sep. 30, 2020	4,233.7			449.4	10,227.8	(4,879.0)		(1,609.1)	44.6
Beginning balance at Jun. 30, 2020	4,175.6			449.3	10,213.6	(4,876.0)		(1,645.8)	34.5
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	6.4					(3.9)			10.3
Other comprehensive income (loss)	38.2							36.7	1.5
Issuance of ordinary shares	0.1			0.1
Share-based compensation (Note 15)	14.2				14.2
Other	(0.8)					0.9			(1.7)
Ending balance at Sep. 30, 2020	4,233.7			449.4	10,227.8	(4,879.0)		(1,609.1)	44.6
Beginning balance at Dec. 31, 2020	4,214.3			449.5	10,242.4	(4,915.2)		(1,622.5)	60.1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	176.4					169.0			7.4
Other comprehensive income (loss)	(8.2)							(6.7)	(1.5)
Issuance of ordinary shares	1.1			1.1
Share-based compensation (Note 15)	18.4				18.4
Spin-off of Technip Energies (Note 2)		$ (857.3)			(1,108.4)			271.0	(19.9)
Accrued distributions to non-controlling interest	(15.0)					0.0			(15.0)
Other	(10.3)					(1.5)			(8.8)
Ending balance at Sep. 30, 2021	3,519.4			450.6	9,152.4	(4,747.7)		(1,358.2)	22.3
Beginning balance at Jun. 30, 2021	3,629.3			450.6	9,144.7	(4,714.0)		(1,294.9)	42.9
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(30.6)					(32.2)			1.6
Other comprehensive income (loss)	(64.7)							(63.3)	(1.4)
Share-based compensation (Note 15)	7.7				7.7
Accrued distributions to non-controlling interest		$ (15.0)			0.0			0.0	(15.0)
Other	(7.3)					(1.5)			(5.8)
Ending balance at Sep. 30, 2021	$ 3,519.4			$ 450.6	$ 9,152.4	$ (4,747.7)		$ (1,358.2)	$ 22.3