Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Number of shares authorized for issuance under share-based payment arrangement.

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SHARE-BASED COMPENSATION - (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Feb. 17, 2021	Feb. 16, 2021	Jan. 11, 2017
Share-based Compensation Arrangement by Share-based Payment Award
Number of additional shares authorized (in shares)						11,900,000
TechnipFMC plc Incentive Award Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares authorized (in shares)					15,200,000		24,100,000
Stock-based compensation expense for nonvested stock units	$ 7.7	$ 14.2	$ 18.4	$ 52.6