IMPAIRMENT, RESTRUCTURING AND OTHER EXPENSES - Restructuring and Other Expenses (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]
Restructuring and other charges	$ 6.0	$ 9.4	$ 13.9	$ 53.7
COVID-19 expenses		21.1		57.8
Subsea
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	5.6	7.1	10.0	36.1
COVID-19 expenses		18.7		50.1
Surface Technologies
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	0.0	0.9	3.5	14.0
COVID-19 expenses		2.4		7.7
Corporate and other
Restructuring Cost and Reserve [Line Items]
Restructuring and other charges	$ 0.4	1.4	$ 0.4	3.6
COVID-19 expenses		$ 0.0		$ 0.0