| Mar 31,
2019 | Mar 31,
2020 | Mar 31,
2021 | Mar 31,
2022 | Mar 31,
2023 | Mar 31,
2024 |
|---|
| Cash and deposits | - | 372 | 948 | 1,067 | 2,240 | 688 |
|---|
| Accounts receivable - trade | - | 63 | 100 | 138 | 229 | 95 |
|---|
| Finished goods | - | 17 | 13 | 17 | 80 | 493 |
|---|
| Work in process | - | 72 | 67 | 129 | 335 | 512 |
|---|
| Supplies | - | 19 | 24 | 25 | 40 | 69 |
|---|
| Prepaid expenses | - | 8 | 12 | 19 | 14 | 31 |
|---|
| Other | - | 34 | 22 | 23 | 24 | 9 |
|---|
| Current assets | - | 585 | 1,186 | 1,419 | 2,962 | 1,897 |
|---|
| Buildings | - | 108 | 115 | 203 | 996 | 1,070 |
|---|
| Accumulated depreciation | - | -33 | -41 | -41 | -71 | -129 |
|---|
| Buildings, net | - | 75 | 74 | 161 | 926 | 940 |
|---|
| Structures | - | 0 | 0 | 0 | 33 | 34 |
|---|
| Accumulated depreciation | - | -0 | -0 | -0 | -2 | -5 |
|---|
| Structures, net | - | 0 | 0 | 0 | 31 | 29 |
|---|
| Machinery and equipment | - | 1,598 | 1,833 | 2,102 | 3,297 | 3,735 |
|---|
| Accumulated depreciation | - | -785 | -909 | -1,044 | -1,321 | -1,461 |
|---|
| Machinery and equipment, net | - | 813 | 924 | 1,059 | 1,977 | 2,274 |
|---|
| Tools, furniture and fixtures | - | 4 | 6 | 10 | 15 | 20 |
|---|
| Accumulated depreciation | - | -2 | -3 | -4 | -6 | -9 |
|---|
| Tools, furniture and fixtures, net | - | 2 | 3 | 6 | 9 | 11 |
|---|
| Construction in progress | - | 8 | 1 | 110 | 23 | 12 |
|---|
| Property, plant and equipment | - | 898 | 1,002 | 1,336 | 2,966 | 3,266 |
|---|
| Software | - | 6 | 7 | 5 | 5 | 3 |
|---|
| Other | - | - | - | 1 | 1 | 1 |
|---|
| Intangible assets | - | 6 | 7 | 6 | 6 | 5 |
|---|
| Shares of subsidiaries and associates | - | - | - | - | - | 110 |
|---|
| Long-term prepaid expenses | - | 1 | 1 | 4 | 5 | 7 |
|---|
| Deferred tax assets | - | 30 | 55 | 12 | 35 | 11 |
|---|
| Guarantee deposits | - | 29 | 29 | 42 | 42 | 42 |
|---|
| Investments and other assets | - | 60 | 85 | 57 | 82 | 170 |
|---|
| Non-current assets | - | 964 | 1,094 | 1,399 | 3,054 | 3,441 |
|---|
| Assets | - | 1,549 | 2,280 | 2,818 | 6,016 | 5,338 |
|---|
| Accounts payable - trade | - | 10 | 11 | 18 | 23 | 3 |
|---|
| Current portion of long-term borrowings | - | 49 | 190 | 90 | 118 | 84 |
|---|
| Accounts payable - other | - | 157 | 62 | 96 | 152 | 70 |
|---|
| Accrued expenses | - | 7 | 12 | 16 | 22 | 28 |
|---|
| Income taxes payable | - | 12 | 46 | 89 | 371 | 14 |
|---|
| Advances received | - | 10 | 2 | 3 | 1 | 2 |
|---|
| Deposits received | - | 1 | 2 | 4 | 6 | 3 |
|---|
| Provision for bonuses | - | 5 | 10 | 23 | 22 | 16 |
|---|
| Provision for bonuses for directors (and other officers) | - | 1 | 10 | 18 | 25 | - |
|---|
| Other | - | 0 | 0 | 0 | 0 | 0 |
|---|
| Current liabilities | - | 252 | 344 | 357 | 741 | 220 |
|---|
| Long-term borrowings | - | 363 | 262 | 350 | 232 | 148 |
|---|
| Provision for retirement benefits | - | 1 | 1 | 2 | 11 | 15 |
|---|
| Asset retirement obligations | - | 37 | 38 | 63 | 103 | 104 |
|---|
| Non-current liabilities | - | 402 | 301 | 415 | 345 | 267 |
|---|
| Liabilities | - | 653 | 645 | 772 | 1,086 | 487 |
|---|
| Share capital | - | 234 | 477 | 495 | 1,484 | 1,500 |
|---|
| Legal capital surplus | - | 203 | 446 | 464 | 1,452 | 1,468 |
|---|
| Other capital surplus | - | 561 | 561 | 561 | 561 | 561 |
|---|
| Capital surplus | - | 764 | 1,007 | 1,025 | 2,013 | 2,029 |
|---|
| Retained earnings brought forward | - | -103 | 151 | 525 | 1,435 | 1,324 |
|---|
| Retained earnings | - | -103 | 151 | 525 | 1,435 | 1,324 |
|---|
| Treasury shares | - | - | - | - | -2 | -2 |
|---|
| Shareholders' equity | - | 896 | 1,635 | 2,045 | 4,931 | 4,851 |
|---|
| Net assets | 718 | 896 | 1,635 | 2,045 | 4,931 | 4,851 |
|---|
| Liabilities and net assets | - | 1,549 | 2,280 | 2,818 | 6,016 | 5,338 |
|---|