Equity Method Investments (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Schedule of Equity Method Investments
Income from equity affiliates	$ 25.9	$ 16.4	$ 54.0	$ 70.6
Revenue	624.2	250.7	1,693.4	792.8
Gross profit	76.6	51.7	167.4	163.0
Net income (loss)	46.1	34.2	(60.9)	97.0
Current assets	1,498.2		1,498.2		$ 1,217.0
Noncurrent assets	4,364.8		4,364.8		4,026.7
Current liabilities	1,740.7		1,740.7		1,511.9
Noncurrent liabilities	1,475.9		1,475.9		$ 1,177.2
Subsea
Schedule of Equity Method Investments
Income from equity affiliates	23.3	15.7	49.5	52.0
Onshore/Offshore
Schedule of Equity Method Investments
Income from equity affiliates	$ 2.6	$ 0.7	$ 4.5	$ 18.6