Related Party Transactions (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Transaction [Line Items]
Trade receivables	$ 76.8	$ 61.7
Trade payables	51.1	148.6
Note receivables	65.2	130.0
Revenue	379.6	293.3	$ 238.1
Expenses	142.4	154.7	141.4
TP JGC Coral France SNC \| Equity Method Investee
Related Party Transaction [Line Items]
Trade receivables	40.1	31.6
Revenue	110.4	118.2	69.9
Expenses	5.0	0.0	0.0
Jumbo Shipping [Member] \| Director
Related Party Transaction [Line Items]
Expenses	4.5
TTSJV W.L.L. [Member] \| Equity Method Investee
Related Party Transaction [Line Items]
Trade receivables	22.4	0.0
Revenue	127.9	0.0	0.0
Techdof Brasil AS \| Equity Method Investee
Related Party Transaction [Line Items]
Revenue	8.3	7.0	0.0
Technip Odebrecht PLSV CV
Related Party Transaction [Line Items]
Trade receivables		10.9
Technip Odebrecht PLSV CV \| Equity Method Investee
Related Party Transaction [Line Items]
Revenue	11.9	7.2	0.0
Anadarko Petroleum Company [Member]
Related Party Transaction [Line Items]
Revenue	67.1
Anadarko Petroleum Company [Member] \| Director
Related Party Transaction [Line Items]
Trade receivables		4.9
Trade payables		0.7
Revenue		124.8	111.3
Dofcon Navegacao Ltda \| Equity Method Investee
Related Party Transaction [Line Items]
Trade payables	2.1	2.5
Revenue	8.4	2.9	0.0
Chiyoda
Related Party Transaction [Line Items]
Trade payables	24.8	70.0
Expenses	25.1	53.0	44.1
JGC Corporation
Related Party Transaction [Line Items]
Trade payables	15.1	69.5
Revenue	6.7	0.0	0.0
Expenses	20.8	81.2	46.8
Serimax Holdings SAS \| Equity Method Investee
Related Party Transaction [Line Items]
Expenses	17.7	0.1	0.0
IFP Energies nouvelles \| Director
Related Party Transaction [Line Items]
Trade payables	2.4	2.4
Expenses	3.8	4.4
Creowave OY [Member]
Related Party Transaction [Line Items]
Expenses	2.6	1.9	4.7
Amaja Oil [Member]
Related Party Transaction [Line Items]
Expenses	2.0
Altus Intervention [Member] \| Director
Related Party Transaction [Line Items]
Expenses	1.8
Competentia [Member] \| Director
Related Party Transaction [Line Items]
Expenses	1.6
Arkema S.A. \| Director
Related Party Transaction [Line Items]
Revenue	8.8
Expenses	18.9	2.6
Magma Global Limited \| Equity Method Investee
Related Party Transaction [Line Items]
Trade payables		0.6
Expenses	7.3	3.0
Others \| Other Affiliates
Related Party Transaction [Line Items]
Trade receivables	14.3	14.3
Trade payables	6.7	2.9
Revenue	30.1	33.2	56.9
Expenses	$ 31.3	$ 8.5	$ 45.8

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

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For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

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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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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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