Derivative financial instruments and market risks - Disclosure of Actual or Potential Effects of Netting Arrangements (Details) - EUR (€) € in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Derivative financial assets
Disclosure of Offsetting of Financial Assets and Liabilities [line items]
Gross carrying amounts before offset	€ 217	€ 201	€ 206
Gross amounts offset (in accordance with IAS 32)	0	0	0
Net amounts as reported in the balance sheet	217	201	206
Net exposure	16	30	46
Derivative financial assets \| Effects of other netting arrangements not fulfilling the IAS 32 criteria for offsetting
Disclosure of Offsetting of Financial Assets and Liabilities [line items]
Fair value of financial collateral
Financial instruments	(201)	(171)	(160)
Derivative financial liabilities
Disclosure of Offsetting of Financial Assets and Liabilities [line items]
Gross carrying amounts before offset	(458)	(291)	(326)
Gross amounts offset (in accordance with IAS 32)	0	0	0
Net amounts as reported in the balance sheet	(458)	(291)	(326)
Net exposure	(257)	(120)	(166)
Derivative financial liabilities \| Effects of other netting arrangements not fulfilling the IAS 32 criteria for offsetting
Disclosure of Offsetting of Financial Assets and Liabilities [line items]
Fair value of financial collateral
Financial instruments	€ 201	€ 171	€ 160

Derivative financial assets and liabilities gross amounts offset in accordance with IAS 32.

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Derivative financial assets and liabilities gross carrying amounts before offset.

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Disclosure of offsetting of financial assets and liabilities.

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Effects of other netting arrangements not fulfilling the IAS32 criteria for offsetting fair value of financial collateral.

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Effects of other netting arrangements not fulfilling the IAS32 criteria for offsetting financial instruments.

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Net amounts as reported in the balance sheet.

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Net exposure

No definition available.

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