Employment benefit plans - Summary of Change in Present Value of Defined Benefit Obligation (Detail) - Defined Benefit Gratuity Plan [Member] ₨ in Millions, $ in Millions |
12 Months Ended | |||
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Mar. 31, 2026
INR (₨)
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Mar. 31, 2026
USD ($)
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Mar. 31, 2025
INR (₨)
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Mar. 31, 2024
INR (₨)
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| Changes in the present value of the defined benefit obligation | ||||
| Opening defined benefit obligation | ₨ 315 | $ 3 | ₨ 300 | ₨ 231 |
| Current service cost | 93 | 1 | 95 | 73 |
| Past service cost | 102 | 1 | 0 | 0 |
| Interest cost | 23 | 1 | 20 | 16 |
| Benefits paid | (44) | 0 | (50) | (34) |
| Remeasurements during the year due to: | ||||
| - Experience adjustments | 52 | 1 | (8) | 10 |
| - Change in financial assumptions | (3) | (0) | 9 | 4 |
| - Change in demographic assumptions | (6) | (0) | (51) | 0 |
| Closing defined benefit obligation | ₨ 532 | $ 6 | ₨ 315 | ₨ 300 |
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in demographic assumptions that result in remeasurements of the net defined benefit liability (asset). Demographic assumptions deal with matters such as: (a) mortality; (b) rates of employee turnover, disability and early retirement; (c) the proportion of plan members with dependants who will be eligible for benefits; (d) the proportion of plan members who will select each form of payment option available under the plan terms; and (e) claim rates under medical plans. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from changes in financial assumptions that result in remeasurements of the net defined benefit liability (asset). Financial assumptions deal with items such as: (a) the discount rate; (b) benefit levels, excluding any cost of the benefits to be met by employees, and future salary; (c) in the case of medical benefits, future medical costs, including claim handling costs (ie the costs that will be incurred in processing and resolving claims, including legal and adjuster's fees); and (d) taxes payable by the plan on contributions relating to service before the reporting date or on benefits resulting from that service. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The decrease (increase) in a net defined benefit liability (asset) resulting from actuarial gains (losses) arising from experience adjustments that result in remeasurements of the net defined benefit liability (asset). Experience adjustments deal with the effects of differences between the previous actuarial assumptions and what has actually occurred. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from employee service in the current period. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- References Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The increase (decrease) in the net defined benefit liability (asset) resulting from past service cost. Past service cost is the change in the present value of the defined benefit obligation for employee service in prior periods, resulting from a plan amendment (the introduction or withdrawal of, or changes to, a defined benefit plan) or a curtailment (a significant reduction by the entity in the number of employees covered by a plan). [Refer: Net defined benefit liability (asset); Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The decrease (increase) in the net defined benefit liability (asset) resulting from payments from the plan. [Refer: Net defined benefit liability (asset)] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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