Retirement benefits - Net Pension Cost (Detail) - Pension ₨ in Millions, $ in Millions |
12 Months Ended | |||
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Mar. 31, 2025
INR (₨)
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Mar. 31, 2025
USD ($)
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Mar. 31, 2024
INR (₨)
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Mar. 31, 2023
INR (₨)
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| Defined Benefit Plan Disclosure [Line Items] | ||||
| Service cost | ₨ 28.4 | $ 0.3 | ₨ 16.0 | ₨ 18.5 |
| Interest cost | 71.6 | 0.8 | 76.4 | 57.3 |
| Expected return on plan assets | (10.5) | (0.1) | (6.5) | (0.4) |
| Actuarial (gains)/losses | 273.4 | 3.2 | (33.4) | 219.2 |
| Net pension cost | ₨ 362.9 | $ 4.2 | ₨ 52.5 | ₨ 294.6 |
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- Definition Defined benefit plan net periodic benefit cost credit increase decrease for plan amendment and service cost. No definition available.
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Details
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