Derivative Financial Instruments and Risk Management Policies - Derivatives Policy (Details) € in Millions	12 Months Ended
Dec. 31, 2023 EUR (€) type_of_hedge	Dec. 31, 2022 EUR (€)
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Notional amount \| €	€ 81,097	€ 83,706
Decrease in outstanding derivatives (as a percent)	3.00%
Number of types of hedges \| type_of_hedge	3
Interest rate risk \| Cash flow hedges
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Average interest rate (as a percent)	4.00%
Interest rate risk \| Cash flow hedges \| Minimum
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Average interest rate (as a percent)	2.00%
Interest rate risk \| Cash flow hedges \| Maximum
Disclosure of information about terms and conditions of hedging instruments and how they affect future cash flows [line items]
Average interest rate (as a percent)	4.00%

The average rate of a hedging instrument. [Refer: Hedging instruments [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-IssueDate 2023-01-01
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Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
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-IssueDate 2023-01-01
-Paragraph 112
-Subparagraph c
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-URIDate 2023-03-23

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Number of types of hedges

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Percentage Increase (Decrease) In Outstanding Derivatives

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