Equity Method Investments (Summarized Financial Information) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Revenues	[1]	$ 6,782.9
Gross profit	[1]	461.0
Net income (loss)	[1]	(348.4)
Magma Global Limited
Schedule of Equity Method Investments [Line Items]
Ownership percentage			25.00%
Yamal
Schedule of Equity Method Investments [Line Items]
Current liabilities	[1]	3,800.0
Noncurrent liabilities	[1]	191.2
Net income (loss)	[1]	7.7
Cash | Yamal
Schedule of Equity Method Investments [Line Items]
Current assets	[1]	3,500.0
Advances to suppliers | Yamal
Schedule of Equity Method Investments [Line Items]
Current assets	[1]	601.7
Intangible assets | Yamal
Schedule of Equity Method Investments [Line Items]
Noncurrent assets	[1]	$ 71.1

[1] As discussed above, in the fourth quarter of 2016, we obtained the voting control interests of legal Onshore/Offshore entities that own and account for the design, engineering and construction of Yamal. As a result of the acquisition and consolidation, we recorded $3.5 billion in cash, $601.7 million in advances to suppliers, $71.1 million in intangibles, $3.8 billion in current liabilities, $191.2 million in noncurrent liabilities, and a $7.7 million gain.