Business Segments (Segment Operating Capital Employed And Segment Assets) (Details) - USD ($) $ in Millions		Sep. 30, 2020	Dec. 31, 2019
Segment Reporting Information
Total assets		$ 18,911.2	$ 23,518.8
Operating Segments
Segment Reporting Information
Total assets		13,365.8	17,519.4
Operating Segments | Subsea
Segment Reporting Information
Total assets		7,218.6	10,824.2
Operating Segments | Technip Energies
Segment Reporting Information
Total assets		4,696.7	4,448.8
Operating Segments | Surface Technologies
Segment Reporting Information
Total assets		1,450.5	2,246.4
Corporate
Segment Reporting Information
Total assets	[1]	$ 5,545.4	$ 5,999.4

[1] Corporate includes cash, deferred income tax balances, property, plant and equipment not associated with a specific segment, pension assets and the fair value of derivative financial instruments.