Goodwill and Intangible Assets Goodwill and Intangibles (Carrying Amount of Goodwill) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Goodwill [Rollforward]
Goodwill	$ 2,461.0	$ 5,598.3
Goodwill, Impairment Loss	3,083.4
Goodwill, Foreign Currency Translation Gain (Loss)	(53.9)
Subsea
Goodwill [Rollforward]
Goodwill		2,814.1
Goodwill, Transfers	(21.2)
Goodwill, Impairment Loss	2,747.5
Goodwill, Foreign Currency Translation Gain (Loss)	(45.4)
Technip Energies
Goodwill [Rollforward]
Goodwill	2,461.0	2,423.6
Goodwill, Transfers	46.1
Goodwill, Foreign Currency Translation Gain (Loss)	(8.7)
Surface Technologies
Goodwill [Rollforward]
Goodwill		$ 360.6
Goodwill, Transfers	(24.9)
Goodwill, Impairment Loss	335.9
Goodwill, Foreign Currency Translation Gain (Loss)	$ 0.2

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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