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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		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Related Party Transaction [Line Items]
Trade receivables	$ 93.3		$ 93.3		$ 61.7
Trade payables	46.8		46.8		148.6
Revenue	92.3	$ 72.8	318.5	$ 225.6
Expenses	29.8	30.1	107.6	66.8
TP JGC Coral France SNC \| Equity Method Investee
Related Party Transaction [Line Items]
Trade receivables	38.9		38.9		31.6
Revenue	17.7	26.4	95.4	87.8
TTSJV W.L.L. \| Equity Method Investee
Related Party Transaction [Line Items]
Trade receivables	27.4		27.4		0.0
Revenue	27.9	0.0	107.4	0.0
Technip Odebrecht PLSV CV \| Equity Method Investee
Related Party Transaction [Line Items]
Trade receivables	11.3		11.3		10.9
Revenue	2.1	0.0	6.1	0.0
Storengy \| Board of Directors Chairman
Related Party Transaction [Line Items]
Revenue	3.7		5.0
Serimax Holdings SAS \| Equity Method Investee
Related Party Transaction [Line Items]
Expenses		0.0	17.7	0.0
Chiyoda
Related Party Transaction [Line Items]
Trade payables	25.3		25.3		70.0
Chiyoda \| Equity Method Investee
Related Party Transaction [Line Items]
Expenses	7.7	3.2	25.3	14.3
JGC Corporation
Related Party Transaction [Line Items]
Trade payables	15.0		15.0		69.5
JGC Corporation \| Equity Method Investee
Related Party Transaction [Line Items]
Revenue	0.4	0.0	6.4	0.0
Expenses	1.0	19.6	19.9	39.2
Arkema S.A. \| Equity Method Investee
Related Party Transaction [Line Items]
Expenses	6.4	0.0	16.2	0.0
IFP Energies nouvelles \| Board of Directors Chairman
Related Party Transaction [Line Items]
Trade payables	1.2		1.2		2.4
Expenses	1.8	0.8	2.8	3.1
Creowave OY \| Equity Method Investee
Related Party Transaction [Line Items]
Expenses	2.0		2.0
Amaja Oil \| Equity Method Investee
Related Party Transaction [Line Items]
Expenses	1.9		1.9
Jumbo Shipping \| Board of Directors Chairman
Related Party Transaction [Line Items]
Expenses			1.8
Altus Intervention \| Board of Directors Chairman
Related Party Transaction [Line Items]
Revenue	3.9	0.0	3.9	0.0
Expenses	1.4		1.4
Competentia \| Board of Directors Chairman
Related Party Transaction [Line Items]
Expenses	0.8		1.3
Dofcon Navegacao \| Equity Method Investee
Related Party Transaction [Line Items]
Trade payables	0.2		0.2		2.5
Revenue	1.4	0.0	7.1	0.0
Magma Global Limited \| Equity Method Investee
Related Party Transaction [Line Items]
Trade payables					0.6
Magma Global Limited \| Board of Directors Chairman
Related Party Transaction [Line Items]
Expenses		0.0	3.2	0.0
Anadarko Petroleum Company \| Equity Method Investee
Related Party Transaction [Line Items]
Trade payables	0.1		0.1		0.7
Revenue	26.3	33.6	67.1	109.1
Anadarko Petroleum Company \| Board of Directors Chairman
Related Party Transaction [Line Items]
Trade receivables	4.5		4.5		4.9
Techdof Brasil AS \| Equity Method Investee
Related Party Transaction [Line Items]
Revenue	5.2		8.5	0.0
Others \| Other Affiliates
Related Party Transaction [Line Items]
Trade receivables	11.2		11.2		14.3
Trade payables	5.0		5.0		$ 2.9
Revenue	3.7	12.8	11.6	28.7
Expenses	$ 6.8	$ 6.5	$ 14.1	$ 10.2