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Financial Risk Management - Summary of Impact on Profit and Equity (before tax effect) of a 10 % strengthening of the US Dollar versus the Euro for US Dollar functional currency (Detail) - 10% strengthening US Dollar/Euro [member] € in Millions | 12 Months Ended
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Dec. 31, 2018 EUR (€)
Disclosure of nature and extent of risks arising from financial instruments [line items] |
Effect on profit before tax | € (5)
Effect on pretax equity | € 7

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- Definition Foreign exchange sensitivity effect on pretax equity. + References No definition available. + Details
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- Definition Foreign exchange sensitivity effect on profit before tax. + References No definition available. + Details
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Namespace Prefix: | cstm_
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Balance Type: | credit
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table. + References No definition available. + Details
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- Details
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