| Mar 31,
2019 | Mar 31,
2020 | Mar 31,
2021 | Mar 31,
2022 | Mar 31,
2023 | Mar 31,
2024 |
|---|
| Cash and deposits | - | 3,170 | 3,599 | 4,645 | 4,774 | 7,134 |
|---|
| Accounts receivable - trade | - | 44 | 46 | 357 | 33 | 45 |
|---|
| Real estate for sale | - | 6,614 | 8,349 | 5,882 | 3,741 | 4,362 |
|---|
| Real estate for sale in process | - | 6,132 | 7,809 | 8,193 | 10,802 | 13,024 |
|---|
| Other | - | 496 | 751 | 509 | 554 | 949 |
|---|
| Prepaid expenses | - | - | - | - | 503 | 498 |
|---|
| Allowance for doubtful accounts | - | -5 | -5 | -0 | -0 | -0 |
|---|
| Other | - | 496 | 751 | 509 | 554 | 949 |
|---|
| Current assets | - | 16,450 | 20,549 | 19,586 | 19,902 | 25,514 |
|---|
| Allowance for doubtful accounts | - | -5 | -5 | -0 | -0 | -0 |
|---|
| Current assets | - | 16,450 | 20,549 | 19,586 | 19,902 | 25,514 |
|---|
| Buildings and structures, net | - | 6,461 | 6,137 | 5,642 | 6,779 | 7,702 |
|---|
| Buildings, net | - | - | - | - | 5,862 | 6,717 |
|---|
| Machinery, equipment and vehicles, net | - | 117 | 98 | 96 | 79 | 76 |
|---|
| Structures, net | - | - | - | - | 25 | 18 |
|---|
| Land | - | 11,754 | 9,909 | 10,964 | 12,312 | 13,063 |
|---|
| Machinery and equipment, net | - | - | - | - | 68 | 55 |
|---|
| Leased assets, net | - | 2 | 16 | 14 | 12 | 26 |
|---|
| Vehicles, net | - | - | - | - | 8 | 19 |
|---|
| Construction in progress | - | 71 | - | 49 | 238 | 52 |
|---|
| Tools, furniture and fixtures, net | - | - | - | - | 13 | 30 |
|---|
| Other, net | - | 8 | 19 | 13 | 17 | 33 |
|---|
| Land | - | 11,754 | 9,909 | 10,964 | 12,312 | 13,063 |
|---|
| Property, plant and equipment | - | 18,412 | 16,179 | 16,778 | 19,436 | 20,951 |
|---|
| Leased assets, net | - | 2 | 16 | 14 | 12 | 26 |
|---|
| Construction in progress | - | 71 | - | 49 | 238 | 52 |
|---|
| Property, plant and equipment | - | 18,412 | 16,179 | 16,778 | 19,436 | 20,951 |
|---|
| Goodwill | - | 398 | 359 | 259 | 1,086 | 1,105 |
|---|
| Leased assets | - | 22 | 15 | 9 | 3 | - |
|---|
| Software | - | - | - | - | 3 | 7 |
|---|
| Other | - | 6 | 8 | 5 | 6 | 123 |
|---|
| Software in progress | - | - | - | - | 2 | - |
|---|
| Intangible assets | - | 425 | 382 | 272 | 1,094 | 1,228 |
|---|
| Leased assets | - | 22 | 15 | 9 | 3 | - |
|---|
| Intangible assets | - | 425 | 382 | 272 | 1,094 | 1,228 |
|---|
| Investment securities | - | 166 | 179 | 156 | 184 | 419 |
|---|
| Shares of subsidiaries and associates | - | - | - | - | 1,031 | 2,226 |
|---|
| Long-term loans receivable | - | 17 | 15 | 14 | 11 | 9 |
|---|
| Investments in capital | - | - | - | - | 30 | 30 |
|---|
| Deferred tax assets | - | 1 | 1 | 1 | 12 | 44 |
|---|
| Long-term loans receivable | - | 17 | 15 | 14 | 11 | 9 |
|---|
| Other | - | 847 | 1,039 | 1,084 | 1,201 | 949 |
|---|
| Long-term prepaid expenses | - | - | - | - | 59 | 66 |
|---|
| Investments and other assets | - | 1,031 | 1,234 | 1,255 | 1,409 | 1,421 |
|---|
| Other | - | 847 | 1,039 | 1,084 | 1,201 | 949 |
|---|
| Investments and other assets | - | 1,031 | 1,234 | 1,255 | 1,409 | 1,421 |
|---|
| Non-current assets | - | 19,869 | 17,795 | 18,305 | 21,537 | 23,600 |
|---|
| Assets | - | 36,319 | 38,344 | 37,891 | 41,440 | 49,113 |
|---|
| Notes payable - trade | - | - | - | - | 459 | 2,017 |
|---|
| Notes and accounts payable - trade | - | 1,870 | 3,171 | 3,267 | 929 | 2,956 |
|---|
| Accounts payable - trade | - | - | - | - | 291 | 916 |
|---|
| Short-term borrowings | - | 4,017 | 4,120 | 3,349 | 1,238 | 5,250 |
|---|
| Short-term borrowings | - | 4,017 | 4,120 | 3,349 | 1,238 | 5,250 |
|---|
| Current portion of bonds payable | - | 15 | - | - | 130 | 60 |
|---|
| Current portion of long-term borrowings | - | 3,812 | 3,385 | 3,780 | 4,230 | 6,261 |
|---|
| Current portion of bonds payable | - | 15 | - | - | 130 | 60 |
|---|
| Lease liabilities | - | 7 | 9 | 9 | 6 | 7 |
|---|
| Lease liabilities | - | 7 | 9 | 9 | 6 | 7 |
|---|
| Income taxes payable | - | 506 | 48 | 911 | 387 | 796 |
|---|
| Accounts payable - other | - | - | - | - | 219 | 363 |
|---|
| Provision for bonuses | - | 26 | 27 | 39 | 46 | 48 |
|---|
| Accrued expenses | - | - | - | - | 28 | 44 |
|---|
| Other | - | 1,147 | 811 | 1,069 | 968 | 1,007 |
|---|
| Income taxes payable | - | 506 | 48 | 911 | 387 | 796 |
|---|
| Current liabilities | - | 11,399 | 11,572 | 12,424 | 7,934 | 16,385 |
|---|
| Advances received | - | - | - | - | 301 | 306 |
|---|
| Deposits received | - | - | - | - | 43 | 19 |
|---|
| Unearned revenue | - | - | - | - | 170 | 181 |
|---|
| Provision for bonuses | - | 26 | 27 | 39 | 46 | 48 |
|---|
| Other | - | 1,147 | 811 | 1,069 | 968 | 1,007 |
|---|
| Current liabilities | - | 11,399 | 11,572 | 12,424 | 7,934 | 16,385 |
|---|
| Bonds payable | - | 240 | 240 | 540 | 410 | 650 |
|---|
| Long-term borrowings | - | 16,386 | 17,335 | 14,434 | 19,246 | 16,792 |
|---|
| Provision for retirement benefits | - | - | - | - | 52 | 57 |
|---|
| Lease liabilities | - | 17 | 25 | 16 | 11 | 22 |
|---|
| Lease liabilities | - | 17 | 25 | 16 | 11 | 22 |
|---|
| Retirement benefit liability | - | 73 | 49 | 55 | 52 | 57 |
|---|
| Deferred tax liabilities for land revaluation | - | 201 | 207 | 182 | 182 | 182 |
|---|
| Deferred tax liabilities | - | 447 | 598 | 389 | 681 | 540 |
|---|
| Asset retirement obligations | - | 75 | 102 | 102 | 124 | 338 |
|---|
| Deferred tax liabilities for land revaluation | - | 201 | 207 | 182 | 182 | 182 |
|---|
| Deferred tax liabilities | - | 447 | 598 | 389 | 681 | 540 |
|---|
| Asset retirement obligations | - | 75 | 102 | 102 | 124 | 338 |
|---|
| Other | - | 1,741 | 1,702 | 1,653 | 1,952 | 2,184 |
|---|
| Non-current liabilities | - | 19,180 | 20,258 | 17,371 | 22,659 | 20,765 |
|---|
| Liabilities | - | 30,580 | 31,829 | 29,795 | 30,552 | 37,151 |
|---|
| Share capital | - | 45 | 45 | 45 | 836 | 839 |
|---|
| Legal capital surplus | - | - | - | - | 791 | 794 |
|---|
| Capital surplus | - | - | - | - | 791 | 794 |
|---|
| Capital surplus | - | - | - | - | 791 | 794 |
|---|
| Legal retained earnings | - | - | - | - | 5 | 5 |
|---|
| Reserve for tax purpose reduction entry of land | - | - | - | - | 124 | 124 |
|---|
| Reserve for tax purpose reduction entry of buildings | - | - | - | - | 168 | 160 |
|---|
| Retained earnings brought forward | - | - | - | - | 8,943 | 9,928 |
|---|
| Retained earnings | - | 5,707 | 6,484 | 8,059 | 9,260 | 10,300 |
|---|
| Retained earnings | - | 5,707 | 6,484 | 8,059 | 9,260 | 10,300 |
|---|
| Shareholders' equity | - | 5,752 | 6,529 | 8,104 | 10,888 | 11,933 |
|---|
| Valuation difference on available-for-sale securities | - | 6 | 10 | -9 | -2 | 29 |
|---|
| Revaluation reserve for land | - | -18 | -24 | 1 | 1 | 1 |
|---|
| Valuation and translation adjustments | - | -12 | -14 | -8 | -1 | 30 |
|---|
| Net assets | 4,467 | 5,739 | 6,515 | 8,096 | 10,887 | 11,963 |
|---|
| Liabilities and net assets | - | 36,319 | 38,344 | 37,891 | 41,440 | 49,113 |
|---|