Equity Method Investments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Schedule of Equity Method Investments
Income from equity affiliates	$ 17.3	$ 67.4	$ 39.4	$ 72.8
Subsea
Schedule of Equity Method Investments
Income from equity affiliates	18.7	37.1	40.4	27.1
Onshore/Offshore
Schedule of Equity Method Investments
Income from equity affiliates	$ (1.4)	$ 30.3	$ (1.0)	$ 45.7