Provisions for retirement benefit obligations - Principal actuarial assumptions (Details)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Provisions for retirement benefit obligations
Retirement age	65 years	65 years	65 years
Payroll taxes	41.41%	41.41%	41.41%
Salary growth rate	2.00%	2.00%	2.00%
Discount rate	3.40%	3.20%	3.70%
Threshold minimum maturity term for Eurozone AA rated corporate bonds	10 years

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]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 19
-IssueDate 2024-01-01
-Paragraph 144
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=19&code=ifrs-tx-2024-en-r&anchor=para_144&doctype=Standard
-URIDate 2024-03-27

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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]]

+ References

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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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- References

No definition available.

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- Definition

The expected rate of payroll taxes used as a significant actuarial assumption to determine the present value of a defined benefit obligation.

+ References

No definition available.

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- Definition

Threshold minimum maturity term of the investments, considered for determination of discount rate for actuarial assumptions used to determine the present value of a defined benefit obligation.

+ References

No definition available.

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