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FINANCIAL RISK MANAGEMENT - Undiscounted Contractual Financial Assets and Financial Liabilities Values by Relevant Maturity Groupings (Details) - EUR (€) € in Millions	Dec. 31, 2020	Dec. 31, 2019
Disclosure of nature and extent of risks arising from financial instruments [line items]
Leases	€ 195	€ 188
Less than 1 year
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial assets	33	24
Financial liabilities	1,031	1,271
Leases	41
Leases		40
Less than 1 year | Borrowings
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	10	139
Less than 1 year | Interest
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	114	112
Less than 1 year | Net debt derivatives
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	10	4
Less than 1 year | Net cash flows from derivative liabilities related to currencies and commodities
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	32	31
Less than 1 year | Trade payables and other (excluding contract liabilities)
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	824	945
Less than 1 year | Net debt derivatives
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial assets	0	3
Less than 1 year | Net cash flows from derivative assets related to currencies and commodities
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial assets	33	21
Expiring within 5 years
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial assets	13	13
Financial liabilities	1,663	1,146
Leases	110
Leases		113
Expiring within 5 years | Borrowings
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	1,089	589
Expiring within 5 years | Interest
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	398	404
Expiring within 5 years | Net debt derivatives
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	30	0
Expiring within 5 years | Net cash flows from derivative liabilities related to currencies and commodities
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	7	25
Expiring within 5 years | Trade payables and other (excluding contract liabilities)
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	29	15
Expiring within 5 years | Net debt derivatives
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial assets	0	4
Expiring within 5 years | Net cash flows from derivative assets related to currencies and commodities
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial assets	13	9
More than 5 years
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial assets	0	0
Financial liabilities	1,247	1,611
Leases	94
Leases		88
More than 5 years | Borrowings
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	1,093	1,438
More than 5 years | Interest
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	60	85
More than 5 years | Net debt derivatives
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	0	0
More than 5 years | Net cash flows from derivative liabilities related to currencies and commodities
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	0	0
More than 5 years | Trade payables and other (excluding contract liabilities)
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial liabilities	0	0
More than 5 years | Net debt derivatives
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial assets	0	0
More than 5 years | Net cash flows from derivative assets related to currencies and commodities
Disclosure of nature and extent of risks arising from financial instruments [line items]
Financial assets	€ 0	€ 0

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- Definition

Minimum Finance Lease Payments Payable

+ References

No definition available.

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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.

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- Definition

The fair value of financial assets. [Refer: At fair value [member]; Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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-IssueDate 2020-01-01
-Paragraph 25
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- Definition

The fair value of financial liabilities. [Refer: At fair value [member]; Financial liabilities]

+ References

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-IssueDate 2020-01-01
-Paragraph 25
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- Definition

The amount of liabilities related to the entity's leases. Lease is a contract, or part of a contract, that conveys the right to use an underlying asset for a period of time in exchange for consideration.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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-IssueDate 2020-01-01
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