Financial risk management - Summary of Sensitivity Analysis (Detail) - Currency risk [member] - JPY (¥) ¥ in Millions |
Mar. 31, 2026 |
Mar. 31, 2025 |
|---|---|---|
| U.S. dollar [member] | ||
| Disclosure of nature and extent of risks arising from financial instruments [line items] | ||
| Estimated Impact On Profit Loss Before Tax Due To Increase In The Foreign Exchange Rates In Respect Of Financial Instruments Held | ¥ 6,139 | ¥ (14,372) |
| Euro [member] | ||
| Disclosure of nature and extent of risks arising from financial instruments [line items] | ||
| Estimated Impact On Profit Loss Before Tax Due To Increase In The Foreign Exchange Rates In Respect Of Financial Instruments Held | ¥ 465 | ¥ 290 |