Interest-bearing liabilities - Types of hedges (Details) € in Millions	Dec. 31, 2018 EUR (€)
Risk management
Fair values	€ (40)
Cross currency swaps \| May 2019
Risk management
Notional amount	581
Fair values	(29)
Cross currency swaps \| June 2022
Risk management
Notional amount	500
Fair values	(16)
Cross currency swaps \| June 2027
Risk management
Notional amount	500
Fair values	(22)
Cross currency swaps \| May 2039
Risk management
Notional amount	400
Fair values	20
Interest rate swaps \| March 2024
Risk management
Notional amount	600
Fair values	€ 7

The fair value of financial instruments designated as hedging instruments. Hedging instruments are designated derivatives or (for a hedge of the risk of changes in foreign currency exchange rates only) designated non-derivative financial assets or non-derivative financial liabilities whose fair value or cash flows are expected to offset changes in the fair value or cash flows of a designated hedged item. [Refer: At fair value [member]; Derivatives [member]; Derivative financial assets; Derivative financial liabilities; Financial instruments, class [member]; Financial assets; Financial liabilities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2021-01-01
-Name IFRS
-Number 7
-IssueDate 2018-01-01
-Paragraph 22
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-02&anchor=para_22_b&doctype=Standard&book=b
-URIDate 2018-03-16

Name:	ifrs-full_FinancialInstrumentsDesignatedAsHedgingInstrumentsAtFairValue
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant