Investment in associates and joint ventures - Summary of changes in investments in associates and joint ventures (Details) - EUR (€) € in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Disclosure of investments in associates and joint ventures [line items]
Opening balance as at 1 January	€ 1,607
Closing balance	1,184	€ 1,607
Associates and joint ventures
Disclosure of investments in associates and joint ventures [line items]
Opening balance as at 1 January	1,607	1,679
Additions	4	1
Transfers	0	(29)
Revaluations	(25)	35
Share of results	127	209
Dividends received	(76)	(160)
Disposals	(382)	(66)
Impairments	(4)	(9)
Exchange rate differences	(34)	(54)
Other	(33)
Closing balance	€ 1,184	€ 1,607

The increase (decrease) in financial assets resulting from foreign exchange. [Refer: Financial assets]

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The amount of investments in subsidiaries, joint ventures and associates in an entity's separate financial statements. [Refer: Total for all associates [member]; Total for all joint ventures [member]; Total for all subsidiaries [member]; Investments in subsidiaries reported in separate financial statements]

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Additions in investments in associates and joint ventures.

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Disclosure of investments in associates and joint ventures.

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The amount of other changes in investments accounted for using equity method.

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Transfer to and from Investments other assets and liabilities.

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