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FINANCIAL RISK MANAGEMENT - Nominal Value of Currency Derivatives (Details) - Currency risk EUR_ in Millions	Dec. 31, 2020 EUR_
Less than 1 year | Forward derivatives sales - USD/EUR
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	508
Less than 1 year | Forward derivatives sales - EUR/CHF
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	82
Less than 1 year | Forward derivatives sales - EUR/CZK
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	21
Less than 1 year | Forward derivatives sales - Other currencies
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	6
Less than 1 year | Forward derivatives purchases - USD/EUR
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	624
Less than 1 year | Forward derivatives purchases - EUR/CHF
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	128
Less than 1 year | Forward derivatives purchases - EUR/CZK
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	85
Less than 1 year | Forward derivatives purchases - Other currencies
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	0
Over 1 year | Forward derivatives sales - USD/EUR
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	246
Over 1 year | Forward derivatives sales - EUR/CHF
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	26
Over 1 year | Forward derivatives sales - EUR/CZK
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	0
Over 1 year | Forward derivatives sales - Other currencies
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	0
Over 1 year | Forward derivatives purchases - USD/EUR
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	61
Over 1 year | Forward derivatives purchases - EUR/CHF
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	44
Over 1 year | Forward derivatives purchases - EUR/CZK
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	29
Over 1 year | Forward derivatives purchases - Other currencies
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Nominal value	0

X

- 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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- Definition

The nominal amount of a hedging instrument. [Refer: Hedging instruments [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 23B
-Subparagraph a
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_23B_a&doctype=Standard
-URIDate 2020-01-01

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2020-01-01
-Paragraph 24A
-Subparagraph d
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2020-en-r&anchor=para_24A_d&doctype=Standard
-URIDate 2020-01-01

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