IMPAIRMENT, RESTRUCTURING AND OTHER EXPENSES - Goodwill and Long-Lived Assets Impairments Goodwill and Long-Lived Assets Impairments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Restructuring Cost and Reserve [Line Items]
Total impairments	$ 1.3	$ 23.0	$ 20.9	$ 3,244.7
Subsea
Restructuring Cost and Reserve [Line Items]
Total impairments	1.3	17.6	17.6	2,826.6
Surface Technologies
Restructuring Cost and Reserve [Line Items]
Total impairments	0.0	5.4	0.3	418.1
Corporate and other
Restructuring Cost and Reserve [Line Items]
Total impairments	$ 0.0	$ 0.0	$ 3.0	$ 0.0