Stock-based compensation - Summary of The fair value of TMC's shares granted during the period (Detail) - ESOP Trust [Member] |
12 Months Ended | ||
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Mar. 31, 2026
JPY (¥)
shares
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Mar. 31, 2025
JPY (¥)
shares
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Mar. 31, 2024
JPY (¥)
shares
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| Disclosure of terms and conditions of share-based payment arrangement [line items] | |||
| Number of points granted during the period | shares | 220,100 | 0 | 0 |
| Fair value per share on the grant date (Yen) (Note 1) | ¥ | ¥ 2,940 | ¥ 0 | ¥ 0 |
| Vesting conditions | — | — | |
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- Definition The description of the vesting requirements for a type of share-based payment arrangement that existed at any time during the period. An entity with substantially similar types of share-based payment arrangements may aggregate this information. [Refer: Types of share-based payment arrangements [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. No definition available.
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- Definition The number of instruments granted in share-based payment arrangement. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The weighted average fair value at the measurement date of granted equity instruments other than share options. [Refer: Weighted average [member]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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