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FINANCIAL RISK MANAGEMENT - Nominal Value of Commodity Derivatives (Details) - Commodity price risk € in Millions	Dec. 31, 2020 EUR (€)
Less than 1 year | Aluminium
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal amount	€ 238
Less than 1 year | Premium
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal amount	7
Less than 1 year | Copper
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal amount	4
Less than 1 year | Silver
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal amount	2
Less than 1 year | Natural gas
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal amount	4
Less than 1 year | Zinc
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal amount	4
Over 1 year | Aluminium
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal amount	30
Over 1 year | Premium
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal amount	6
Over 1 year | Copper
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal amount	4
Over 1 year | Silver
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal amount	0
Over 1 year | Natural gas
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal amount	1
Over 1 year | Zinc
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal amount	€ 5

X

- Definition

The nominal amount of a credit derivative. [Refer: Derivatives [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 24G
-Subparagraph a
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-URIDate 2020-01-01

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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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