Share-Based Compensation Plans - Summary of Number and Weighted Average Exercise Prices of Other Equity Instruments (Detail) - Equity Based Compensation Plan [Member]	Dec. 31, 2025 shares € / shares	Dec. 31, 2024 shares € / shares
Disclosure Of Number And Weighted Average Exercise Prices Of Other Equity Instruments [Line Items]
Restricted and performance shares outstanding at the end of the year \| shares	6,523,939	4,438,497
Weighted average fair value \| € / shares	€ 4.38	€ 5.51

The number of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2025-01-01
-Paragraph 45
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2025-en-r&anchor=para_45&doctype=Standard
-URIDate 2025-03-27

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- Definition

The weighted average exercise price of other equity instruments (ie other than share options) outstanding in a share-based payment arrangement. [Refer: Weighted average [member]]

+ References

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- Definition

Disclosure of number and weighted average exercise prices of other equity instruments.

+ References

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