IMPAIRMENT, RESTRUCTURING AND OTHER EXPENSES - Restructuring, Settlement and Impairment Provisions (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Restructuring Cost and Reserve [Line Items]
Total impairment, restructuring and other expenses	$ 25.5	$ 3,199.1
Subsea
Restructuring Cost and Reserve [Line Items]
Total impairment, restructuring and other expenses	19.7	2,773.6
Surface Technologies
Restructuring Cost and Reserve [Line Items]
Total impairment, restructuring and other expenses	2.8	424.4
Corporate and other
Restructuring Cost and Reserve [Line Items]
Total impairment, restructuring and other expenses	$ 3.0	$ 1.1