v3.26.1
Property, plant and equipment (Details)
₨ in Millions, $ in Millions
 12 Months Ended
Mar. 31, 2026
INR (₨)
Mar. 31, 2026
USD ($)
Mar. 31, 2025
INR (₨)
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning ₨ 38,915    
Balance at the ending 43,481 $ 459 ₨ 38,915
Freehold [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 207    
Balance at the ending 207   207
Building [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 14,510    
Balance at the ending 16,166   14,510
Plant and machinery [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 13,890    
Balance at the ending 17,424   13,890
Computer equipment [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 314    
Balance at the ending 560   314
Office equipment [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 1,378    
Balance at the ending 1,498   1,378
Fixtures and fittings [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 27    
Balance at the ending 37   27
Vehicles [Member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 2    
Balance at the ending 2   2
Construction in Progress [Member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 8,587    
Balance at the ending 7,587   8,587
Property, plant and equipment [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 30,328    
Balance at the ending 35,894   30,328
Gross carrying amount [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 57,489   42,883
Additions 11,462   15,017
Deletions/Adjustments during the year 9,795 [1]   414
Reclassification [2] 0    
Translation Difference 13   3
Balance at the ending 59,169   57,489
Gross carrying amount [member] | Freehold [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 207   207
Additions 0   0
Deletions/Adjustments during the year 0 [1]   0
Reclassification [2] 0    
Balance at the ending 207   207
Gross carrying amount [member] | Building [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 21,252   13,932
Additions 4,255   7,320
Deletions/Adjustments during the year 747 [1]   0
Reclassification [2] (619)    
Translation Difference 0   0
Balance at the ending 24,141   21,252
Gross carrying amount [member] | Plant and machinery [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 30,456   24,002
Additions 6,129   6,528
Deletions/Adjustments during the year 7,450 [1]   77
Reclassification [2] 619    
Translation Difference 12   3
Balance at the ending 29,766   30,456
Gross carrying amount [member] | Computer equipment [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 2,211   2,184
Additions 437   300
Deletions/Adjustments during the year 1,113 [1]   273
Reclassification [2] 0    
Translation Difference 0    
Balance at the ending 1,535   2,211
Gross carrying amount [member] | Office equipment [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 3,184   2,372
Additions 617   854
Deletions/Adjustments during the year 348 [1]   42
Reclassification [2] 9    
Translation Difference 0    
Balance at the ending 3,462   3,184
Gross carrying amount [member] | Fixtures and fittings [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 166   173
Additions 20   15
Deletions/Adjustments during the year 127 [1]   22
Reclassification [2] (9)    
Translation Difference 1   0
Balance at the ending 51   166
Gross carrying amount [member] | Vehicles [Member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 13   13
Additions 4   0
Deletions/Adjustments during the year 10 [1]   0
Reclassification [2] 0    
Translation Difference 0    
Balance at the ending 7   13
Gross carrying amount [member] | Property, plant and equipment [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 57,489   42,883
Additions 11,462   15,017
Deletions/Adjustments during the year 9,795 [1]   414
Reclassification [2] 0    
Translation Difference 13   3
Balance at the ending 59,169   57,489
Accumulated depreciation and amortisations [Member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 27,161   23,044
Depreciation for the year 5,903   4,449
Deletions/Adjustments during the year 9,795 [1]   333
Reclassification [2] 0    
Translation Difference 6   1
Balance at the ending 23,275   27,161
Accumulated depreciation and amortisations [Member] | Freehold [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 0   0
Depreciation for the year 0   0
Deletions/Adjustments during the year 0 [1]   0
Reclassification [2] 0    
Balance at the ending 0   0
Accumulated depreciation and amortisations [Member] | Building [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 6,742   5,163
Depreciation for the year 1,990   1,579
Deletions/Adjustments during the year 747 [1]   0
Reclassification [2] (10)    
Translation Difference 0   0
Balance at the ending 7,975   6,742
Accumulated depreciation and amortisations [Member] | Plant and machinery [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 16,566   14,319
Depreciation for the year 3,211   2,322
Deletions/Adjustments during the year 7,450 [1]   76
Reclassification [2] 10    
Translation Difference 5   1
Balance at the ending 12,342   16,566
Accumulated depreciation and amortisations [Member] | Computer equipment [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 1,897   1,924
Depreciation for the year 191   166
Deletions/Adjustments during the year 1,113 [1]   193
Reclassification [2] 0    
Translation Difference 0    
Balance at the ending 975   1,897
Accumulated depreciation and amortisations [Member] | Office equipment [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 1,806   1,469
Depreciation for the year 499   379
Deletions/Adjustments during the year 348 [1]   42
Reclassification [2] 7    
Translation Difference 0    
Balance at the ending 1,964   1,806
Accumulated depreciation and amortisations [Member] | Fixtures and fittings [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 139   159
Depreciation for the year 8   2
Deletions/Adjustments during the year 127 [1]   22
Reclassification [2] (7)    
Translation Difference 1   0
Balance at the ending 14   139
Accumulated depreciation and amortisations [Member] | Vehicles [Member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 11   10
Depreciation for the year 4   1
Deletions/Adjustments during the year 10 [1]   0
Reclassification [2] 0    
Translation Difference 0    
Balance at the ending 5   11
Accumulated depreciation and amortisations [Member] | Property, plant and equipment [member]      
Disclosure of detailed information about property, plant and equipment [line items]      
Balance at beginning 27,161   23,044
Depreciation for the year 5,903   4,449
Deletions/Adjustments during the year 9,795 [1]   333
Reclassification [2] 0    
Translation Difference 6   1
Balance at the ending ₨ 23,275   ₨ 27,161
[1] During the year, the Group carried out an evaluation of its assets to assess the future economic benefits expected from its use or disposal. Accordingly, the Group identified the following assets which it assessed did not have any future economic benefits from it's use (or) disposal. These assets have been retired from active use and remain in the custody of the Group pending physical disposal.
[2] The Group has disclosed certain assets which are in the nature of plant and machinery and office equipment along with buildings  and furniture & fixtures respectively. These assets are depreciated over the estimated useful life of plant and machinery and office equipment in accordance with the accounting policy consistently applied by the Group. The Group believes that it is more appropriate to disclose such assets as part of plant and machinery and office equipment rather than as part of buildings and furniture and fixtures. Hence, the cost of such assets and the accumulated depreciation thereon, as on April 1, 2025 has been transferred to the respective category for a better presentation.