Subsequent events - Additional Information (Detail) ₨ / shares in Units, $ / shares in Units, ₨ in Millions, $ in Millions |
Jun. 16, 2026
USD ($)
|
Apr. 18, 2026
$ / shares
|
Apr. 01, 2026
INR (₨)
|
Mar. 31, 2025
₨ / shares
|
Mar. 31, 2024
₨ / shares
|
|---|---|---|---|---|---|
| Subsequent Event [Line Items] | |||||
| Dividends Payable, Amount Per Share | ₨ / shares | ₨ 11 | ₨ 9.75 | |||
| Subsequent Event [Member] | |||||
| Subsequent Event [Line Items] | |||||
| Dividends Payable, Amount Per Share | $ / shares | $ 13 | ||||
| Dividends Payable | ₨ | ₨ 200,113.8 | ||||
| Debt Instrument, Face Amount | $ | $ 750 | ||||
| Debt Instrument, Interest Rate, Stated Percentage | 5.067% | ||||
| Debt Instrument, Maturity Date | Jun. 24, 2031 |
| X | ||||||||||
- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
|
| X | ||||||||||
- Definition The per share amount of a dividend declared, but not paid, as of the financial reporting date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Details
|