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For an unclassified balance sheet, amount of receivables arising from transactions with related parties.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Related Party Transactions Schedule of Related Party Transactions (Tables) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Related Party Transaction [Line Items]
Trade receivables	$ 146.2		$ 146.2		$ 61.7
Trade payables	45.6		45.6		148.6
Revenue	102.5	$ 60.2	226.2	$ 152.7
Expenses	25.1	10.5	77.8	36.7
TP JGC Coral France SNC \| Equity Method Investee
Related Party Transaction [Line Items]
Trade receivables	79.1		79.1		31.6
Revenue	51.0	33.2	77.7	61.4
TTSJV W.L.L. \| Equity Method Investee
Related Party Transaction [Line Items]
Trade receivables	30.6		30.6		0.0
TTSJV W.L.L. \| Board of Directors Chairman
Related Party Transaction [Line Items]
Revenue	22.7	0.0	75.5	0.0
Technip Odebrecht PLSV CV \| Equity Method Investee
Related Party Transaction [Line Items]
Trade receivables	11.2		11.2		10.9
Serimax Holdings SAS \| Equity Method Investee
Related Party Transaction [Line Items]
Expenses	0.2	0.0	17.7	0.0
Chiyoda
Related Party Transaction [Line Items]
Trade payables	21.4		21.4		70.0
Chiyoda \| Equity Method Investee
Related Party Transaction [Line Items]
Expenses	3.4	3.4	17.6	11.1
JGC Corporation
Related Party Transaction [Line Items]
Trade payables	18.7		18.7		69.5
JGC Corporation \| Equity Method Investee
Related Party Transaction [Line Items]
Expenses	4.6	4.5	18.9	19.6
Arkema S.A. \| Equity Method Investee
Related Party Transaction [Line Items]
Expenses	9.8	0.0	9.8	0.0
IFP Energies nouvelles \| Equity Method Investee
Related Party Transaction [Line Items]
Expenses	0.0	1.2	1.0	2.3
IFP Energies nouvelles \| Board of Directors Chairman
Related Party Transaction [Line Items]
Trade payables	2.2		2.2		2.4
Magma Global Limited \| Equity Method Investee
Related Party Transaction [Line Items]
Trade payables	0.6		0.6		0.6
Magma Global Limited \| Board of Directors Chairman
Related Party Transaction [Line Items]
Expenses	1.3	0.0	3.2	0.0
Dofcon Navegacao \| Equity Method Investee
Related Party Transaction [Line Items]
Trade payables	0.2		0.2		2.5
Revenue	1.6	0.0	5.7	0.0
Anadarko Petroleum Company \| Equity Method Investee
Related Party Transaction [Line Items]
Trade payables	0.0		0.0		0.7
Revenue	12.1	25.2	40.8	75.5
Anadarko Petroleum Company \| Board of Directors Chairman
Related Party Transaction [Line Items]
Trade receivables	9.5		9.5		4.9
Others \| Other Affiliates
Related Party Transaction [Line Items]
Trade receivables	15.8		15.8		14.3
Trade payables	2.5		2.5		$ 2.9
Revenue	15.1	1.8	26.5	15.8
Expenses	$ 5.8	$ 1.4	$ 9.6	$ 3.7