Impairment, Restructuring and Other Expense (Details) $ in Millions	1 Months Ended	12 Months Ended
	Jul. 31, 2015 employee	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Restructuring and Impairment [Line Items]
Impairment expense		$ 1,792.6	$ 34.3	$ 38.2
Goodwill, Impairment		1,383.0
Other Asset Impairment Charges		372.9
Charges		38.6	157.2	304.8
Restructuring and impairment expense		1,831.2	191.5	343.0
Restructuring workforce reduction | employee	6,000
Subsea
Restructuring and Impairment [Line Items]
Impairment expense		1,784.2	11.5	23.0
Goodwill, Impairment		(1,383.0)
Charges		17.7	88.4	58.7
Onshore/Offshore
Restructuring and Impairment [Line Items]
Impairment expense				14.6
Charges		(3.4)	27.0	214.4
Surface Technologies
Restructuring and Impairment [Line Items]
Impairment expense		4.5	10.2
Charges		9.3	9.0
Corporate and other
Restructuring and Impairment [Line Items]
Impairment expense		3.9	12.6	0.6
Charges		$ 15.0	$ 32.8	$ 31.7