Financial risk management and financial instruments - Summary of Changes in Warrants Liability (Details) - Warrants - EUR (€) € in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disclosure Of Changes In Warrants Liability [Line Items]
Beginning balance	€ 3	€ 1	€ 72
Changes in fair value recognized in consolidated statement of operations	33	2	(74)
Issuance of ordinary shares upon net settlement of warrants	(36)	0	0
Effect of changes in foreign exchange rates	0	0	3
Ending balance	€ 0	€ 3	€ 1

Disclosure of changes in warrants liability.

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- Definition

Effect of changes in foreign exchange rates on fair value of derivative liabilities.

+ References

No definition available.

+ Details

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- Definition

Increase decrease through exercise or net settlement of warrants equity.

+ References

No definition available.

+ Details

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- Definition

The gains (losses) on financial liabilities at fair value through profit or loss. [Refer: Financial liabilities at fair value through profit or loss]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2024-01-01
-Paragraph 20
-Subparagraph a
-Clause i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2024-en-r&anchor=para_20_a_i&doctype=Standard
-URIDate 2024-03-27

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- Definition

The amount of warrant liabilities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2024-01-01
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2024-en-r&anchor=para_55&doctype=Standard
-URIDate 2024-03-27

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