Equity Method Investments (Percentage Owned and Carrying Value) (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Carrying value	$ 272.5	$ 235.4
Technip Odebrecht PLSV CV
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%
Carrying value	$ 111.4
Dofcon Brasil AS
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%
Carrying value	$ 74.1
Serimax Holdings SAS
Schedule of Equity Method Investments [Line Items]
Ownership percentage	20.00%
Carrying value	$ 25.1
FSTP Brasil Ltda
Schedule of Equity Method Investments [Line Items]
Ownership percentage	25.00%
Carrying value	$ 21.5
Other
Schedule of Equity Method Investments [Line Items]
Carrying value	$ 40.4

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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+ References

No definition available.

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