Employment benefit plans - Summary of Principal Assumptions Used in Defined Benefit Plan (Detail) - Defined Benefit Gratuity Plan [Member]	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
Disclosure of Detailed Information About Principal Assumptions Used in Defined Benefit Plan [Line Items]
Discount rate	6.75%	6.60%	7.20%
Salary escalation	10.00%	10.00%	10.00%

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 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]]

+ References

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- Definition

Disclosure of detailed information about principal assumptions used in defined benefit plan [Line Items].

+ References

No definition available.

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