Retirement benefit obligations - Disclosure of main actuarial assumptions used to measure the retirement benefit obligations (Details)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Disclosure of defined benefit plans [line items]
Discount Rate (IBoxx Corporates AA)	3.70%	3.34%	0.90%
Salary increase rate	3.00%
Turnover rate, average exit rate	2.02%	2.05%
Employee contribution rate	45.00%	45.00%	45.00%
Top of range
Disclosure of defined benefit plans [line items]
Turnover rate			5.80%
Bottom of range
Disclosure of defined benefit plans [line items]
Turnover rate	0.00%	0.00%	0.05%
Key magement
Disclosure of defined benefit plans [line items]
Retirement age	65 years	65 years	65 years
Salary increase rate		3.00%	3.00%
Other employees
Disclosure of defined benefit plans [line items]
Retirement age	64 years	64 years	63 years
Salary increase rate		2.55%	2.55%

Actuarial Assumption Of Employee Contribution Rate

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- Definition

Actuarial Assumption Of Expected Rates Of Turnover

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- Definition

Actuarial Assumption Of Expected Rates Of Turnover, Average Exit Rate

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- Definition

The discount rate used as the significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [domain]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2025-01-01
-Paragraph 144
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2025-en-r&anchor=para_144&doctype=Standard
-URIDate 2025-03-27

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- Definition

The expected rate of salary increases used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit plans [domain]; Defined benefit obligation, at present value; Actuarial assumptions [domain]]

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- Definition

The retirement age used as a significant actuarial assumption to determine the present value of a defined benefit obligation. [Refer: Defined benefit obligation, at present value; Actuarial assumptions [domain]]

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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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No definition available.

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