RELATED PARTY TRANSACTIONS - Trade Payables (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Related Party Transaction [Line Items]
Total accounts payable	$ 222.6	$ 4.6
Technip Energies | Equity Method Investee
Related Party Transaction [Line Items]
Total accounts payable	216.7	0.0
Dofcon Navegacao | Equity Method Investee
Related Party Transaction [Line Items]
Total accounts payable	1.9	1.5
Others | Other Affiliates
Related Party Transaction [Line Items]
Total accounts payable	$ 4.0	$ 3.1