Derivatives and hedge accounting - Movement cash flow hedge reserve (Details) - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disclosure of detailed information about hedged items [line items]
Opening balance	€ (2,767)	€ (2,192)
Income tax	138	251	€ (875)
Exchange rate and other changes	563	(85)	436
Closing balance	(687)	(2,767)	(2,192)
Reserve of cash flow hedges
Disclosure of detailed information about hedged items [line items]
Opening balance	(2,058)	(3,055)	(153)
Value changes recognised in OCI	743	1,922
Amounts recycled to profit or loss	(209)	(325)
Income tax	(140)	(381)
Exchange rate and other changes	(14)	(103)
Adjustment for non controlling interest	(14)	(116)
Movement for the year	365	997
Closing balance	€ (1,693)	€ (2,058)	€ (3,055)

The increase (decrease) in equity. [Refer: Equity]

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No definition available.

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The gains (losses) recognised in other comprehensive income on cash flow hedges, before tax, before reclassification adjustments. [Refer: Cash flow hedges [member]]

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The amount of income tax relating to amounts recognised in other comprehensive income in relation to cash flow hedges. [Refer: Cash flow hedges [member]; Other comprehensive income]

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The increase (decrease) in equity resulting from transactions with owners.

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The amount of other comprehensive income, net of tax, after reclassification adjustments, related to exchange differences when financial statements of foreign operations are translated. [Refer: Other comprehensive income]

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A component of equity representing reserves within equity, not including retained earnings. [Refer: Retained earnings]

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The amount of reclassification adjustments related to cash flow hedges, before tax. Reclassification adjustments are amounts reclassified to profit (loss) in the current period that were recognised in other comprehensive income in the current or previous periods. [Refer: Cash flow hedges [member]; Other comprehensive income]

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