Restructuring and Impairment Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Restructuring and Impairment
Restructuring and impairment expense	$ 9.7	$ 35.7
Subsea
Restructuring and Impairment
Restructuring and impairment expense	6.7	0.3
Onshore/Offshore
Restructuring and Impairment
Restructuring and impairment expense	(0.3)	$ 35.4
Surface Technologies
Restructuring and Impairment
Restructuring and impairment expense	1.4
Corporate and Other
Restructuring and Impairment
Restructuring and impairment expense	$ 1.9