| Mar 31,
2021 | Mar 31,
2022 | Mar 31,
2023 | Mar 31,
2024 |
|---|
| Cash and deposits | - | 757 | 880 | 1,324 |
|---|
| Accounts receivable - trade | - | 152 | 162 | 153 |
|---|
| Work in process | - | 1 | 4 | 5 |
|---|
| Supplies | - | 0 | 0 | 0 |
|---|
| Other | - | 42 | 36 | 36 |
|---|
| Prepaid expenses | - | - | 23 | 22 |
|---|
| Allowance for doubtful accounts | - | -2 | -3 | -3 |
|---|
| Accounts receivable - other | - | - | 2 | 3 |
|---|
| Current assets | - | 950 | 1,080 | 1,515 |
|---|
| Other | - | 42 | 36 | 36 |
|---|
| Allowance for doubtful accounts | - | -2 | -3 | -3 |
|---|
| Current assets | - | 950 | 1,080 | 1,515 |
|---|
| Facilities attached to buildings | - | 11 | 11 | 11 |
|---|
| Tools, furniture and fixtures | - | 5 | 5 | 2 |
|---|
| Leased assets | - | - | - | 3 |
|---|
| Accumulated depreciation | - | -8 | -9 | -7 |
|---|
| Property, plant and equipment | - | 10 | 8 | 10 |
|---|
| Software | - | 17 | 22 | 17 |
|---|
| Goodwill | - | - | 46 | 31 |
|---|
| Software in progress | - | 8 | 6 | - |
|---|
| Software | - | 17 | 22 | 17 |
|---|
| Intangible assets | - | 24 | 28 | 17 |
|---|
| Software in progress | - | 8 | 6 | - |
|---|
| Intangible assets | - | 24 | 28 | 17 |
|---|
| Investment securities | - | 272 | 418 | 406 |
|---|
| Investments in other securities of subsidiaries and associates | - | - | 15 | 12 |
|---|
| Shares of subsidiaries and associates | - | 15 | 7 | 7 |
|---|
| Leasehold deposits | - | - | 7 | 7 |
|---|
| Deferred tax assets | - | 52 | 65 | 37 |
|---|
| Deferred tax assets | - | 52 | 65 | 37 |
|---|
| Other | - | 8 | 8 | 9 |
|---|
| Long-term prepaid expenses | - | - | 0 | 0 |
|---|
| Allowance for doubtful accounts | - | -0 | -1 | -1 |
|---|
| Distressed receivables | - | - | 1 | 1 |
|---|
| Investments and other assets | - | 348 | 497 | 457 |
|---|
| Allowance for doubtful accounts | - | -0 | -1 | -1 |
|---|
| Investments and other assets | - | 348 | 497 | 457 |
|---|
| Non-current assets | - | 382 | 533 | 484 |
|---|
| Assets | - | 1,332 | 1,613 | 2,000 |
|---|
| Accounts payable - trade | - | 45 | 31 | 30 |
|---|
| Accounts payable - other | - | 78 | 95 | 106 |
|---|
| Income taxes payable | - | 45 | 10 | 39 |
|---|
| Accrued expenses | - | - | 0 | 1 |
|---|
| Unearned revenue | - | 158 | 249 | 264 |
|---|
| Income taxes payable | - | 45 | 10 | 39 |
|---|
| Provision for bonuses | - | 26 | 32 | 31 |
|---|
| Unearned revenue | - | 158 | 249 | 264 |
|---|
| Other | - | 33 | 20 | 40 |
|---|
| Deposits received | - | - | 4 | 9 |
|---|
| Current liabilities | - | 384 | 437 | 509 |
|---|
| Accrued consumption taxes | - | - | 15 | 26 |
|---|
| Lease liabilities | - | - | 0 | 1 |
|---|
| Provision for bonuses | - | 26 | 32 | 31 |
|---|
| Other | - | 33 | 20 | 40 |
|---|
| Current liabilities | - | 384 | 437 | 509 |
|---|
| Lease liabilities | - | - | - | 2 |
|---|
| Asset retirement obligations | - | 2 | 2 | 2 |
|---|
| Asset retirement obligations | - | 2 | 2 | 2 |
|---|
| Other | - | 0 | - | 2 |
|---|
| Non-current liabilities | - | 2 | 2 | 4 |
|---|
| Liabilities | - | 386 | 439 | 513 |
|---|
| Share capital | - | 8 | 8 | 127 |
|---|
| Legal capital surplus | - | - | - | 119 |
|---|
| Capital surplus | - | - | - | 119 |
|---|
| Capital surplus | - | - | - | 119 |
|---|
| Other retained earnings | - | - | 517 | 637 |
|---|
| Retained earnings brought forward | - | - | 517 | 637 |
|---|
| Retained earnings | - | 463 | 547 | 673 |
|---|
| Retained earnings | - | 463 | 547 | 673 |
|---|
| Shareholders' equity | - | 471 | 555 | 920 |
|---|
| Net assets | 815 | 946 | 1,174 | 1,487 |
|---|
| Valuation difference on available-for-sale securities | - | 1 | 3 | 2 |
|---|
| Foreign currency translation adjustment | - | 3 | 15 | 24 |
|---|
| Valuation and translation adjustments | - | 4 | 18 | 27 |
|---|
| Non-controlling interests | - | 471 | 601 | 540 |
|---|
| Net assets | 815 | 946 | 1,174 | 1,487 |
|---|
| Liabilities and net assets | - | 1,332 | 1,613 | 2,000 |
|---|