Share Based Compensation - Summary of Number of Shares and Synthetic Shares (Detail) shares in Millions	12 Months Ended
Dec. 31, 2024 shares
Executive members [member] \| LTV 2024 [member]
Disclosure of terms and conditions of share based payment arrangement [line Items]
Maximum shares required	10.4
Granted shares	4.0
Increase/decrease due to performance condition 2023	0.7
Outstanding ending	4.7
Executive members [member] \| LTV 2023 [member]
Disclosure of terms and conditions of share based payment arrangement [line Items]
Maximum shares required	4.1
Granted shares	3.7
Outstanding beginning	2.0
Forfeited during 2023	(0.2)
Increase/decrease due to performance condition 2023	0.1
Outstanding ending	1.9
Executive members [member] \| LTV 2022 [member]
Disclosure of terms and conditions of share based payment arrangement [line Items]
Maximum shares required	2.0
Granted shares	0.7
Outstanding beginning	0.9
Forfeited during 2023	(0.1)
Increase/decrease due to performance condition 2023	(0.2)
Outstanding ending	0.6
Executive members [member] \| LTV 2021 [member]
Disclosure of terms and conditions of share based payment arrangement [line Items]
Maximum shares required	2.1
Granted shares	0.6
Outstanding beginning	0.5
Exercised during 2023	(0.5)
Executive members [member] \| LTV prior 2021 [Member]
Disclosure of terms and conditions of share based payment arrangement [line Items]
Outstanding beginning	1.7
Exercised during 2023	(1.5)
Forfeited during 2023	(0.2)
Executive members [member] \| Longterm Variable Compensation Program [Member]
Disclosure of terms and conditions of share based payment arrangement [line Items]
Granted shares	4.0
Outstanding beginning	5.1
Exercised during 2023	(2.0)
Forfeited during 2023	(0.5)
Increase/decrease due to performance condition 2023	0.6
Outstanding ending	7.2
The President and CEO [member] \| LTV 2024 [member]
Disclosure of terms and conditions of share based payment arrangement [line Items]
Granted shares	0.5
Increase/decrease due to performance condition 2023	0.1
Outstanding ending	0.6
The President and CEO [member] \| LTV 2023 [member]
Disclosure of terms and conditions of share based payment arrangement [line Items]
Granted shares	0.6
Outstanding beginning	0.3
Outstanding ending	0.3
The President and CEO [member] \| LTV 2022 [member]
Disclosure of terms and conditions of share based payment arrangement [line Items]
Granted shares	0.3
Outstanding beginning	0.4
Increase/decrease due to performance condition 2023	(0.1)
Outstanding ending	0.3
The President and CEO [member] \| LTV 2021 [member]
Disclosure of terms and conditions of share based payment arrangement [line Items]
Granted shares	0.3
Outstanding beginning	0.3
Exercised during 2023	(0.3)
The President and CEO [member] \| LTV prior 2021 [Member]
Disclosure of terms and conditions of share based payment arrangement [line Items]
Outstanding beginning	0.7
Exercised during 2023	(0.7)
The President and CEO [member] \| Longterm Variable Compensation Program [Member]
Disclosure of terms and conditions of share based payment arrangement [line Items]
Granted shares	0.5
Outstanding beginning	1.7
Exercised during 2023	(1.0)
Outstanding ending	1.2

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
-Number 2
-IssueDate 2024-01-01
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2024-01-01
-Paragraph 47
-Subparagraph b
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The number of other equity instruments (ie other than share options) exercised or vested in a share-based payment arrangement.

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- Definition

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

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- Definition

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

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- Definition

The number of shares issued by the entity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
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-IssueDate 2024-01-01
-Paragraph 106
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-URIDate 2024-03-27

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