Debt, cash and cash equivalents - Summary of Changes in Financial Position (Details) - EUR (€) € in Millions	Jun. 30, 2026	Dec. 31, 2025
Cash and cash equivalents [abstract]
Long-term debt	€ 14,646	€ 14,248
Short-term debt and current portion of long-term debt	7,026	4,342
Interest rate and currency derivatives used to manage debt	221	112
Total debt	21,893	18,702
Cash and cash equivalents	(6,350)	(7,657)
Interest rate and currency derivatives used to manage cash and cash equivalents	(30)	(37)
Net debt	15,513	11,008
Lease liabilities	€ 1,904	€ 1,739

The amount of outstanding funds that the entity is obligated to repay.

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The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

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The amount of current borrowings and current portion of non-current borrowings. [Refer: Borrowings]

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The amount of liabilities related to the entity's leases. Lease is a contract, or part of a contract, that conveys the right to use an underlying asset for a period of time in exchange for consideration.

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The non-current portion of non-current borrowings. [Refer: Borrowings]

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Debt net of cash and cash equivalents.

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Interest rate and currency derivatives used to manage cash and cash equivalent.

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Interest rate and currency derivatives used to manage debt.

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