Balance Sheet
| Concept | As at 2025-03-31 | As at 2024-09-30 | 
|---|---|---|
| Balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Current assets | ||
| Cash and deposits | 
                                                1,041,700,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                935,487,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accounts receivable - trade | 
                                                309,929,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                264,892,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Raw materials | 
                                                124,444,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                150,768,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Work in process | 
                                                585,967,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                461,368,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                2,176,909,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,962,792,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                114,867,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                150,276,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Property, plant and equipment | 
                                                1,902,842,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,606,986,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Land | 
                                                889,517,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                889,517,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Construction in progress | 
                                                376,260,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                68,196,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Property, plant and equipment | ||
| Own-used assets | ||
| Tools, furniture and fixtures | 
                                                510,240,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                468,159,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accumulated depreciation | 
                                                -428,989,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -416,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Tools, furniture and fixtures, net | 
                                                81,251,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                52,158,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | ||
| Software | 
                                                31,719,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                29,584,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | 
                                                31,719,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                34,449,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | ||
| Investments and other assets | 
                                                654,880,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                645,505,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax assets | 
                                                60,344,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                43,283,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -88,372,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -86,709,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                198,972,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                198,621,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Distressed receivables | 
                                                19,410,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                19,410,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                2,589,442,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,286,940,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other assets | — | — | 
| Other assets | ||
| Deferred assets | 
                                                28,486,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                21,390,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Business commencement expenses | 
                                                28,486,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                21,390,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred assets | ||
| Assets | 
                                                4,794,838,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,271,124,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | ||
| Short-term borrowings | 
                                                100,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                100,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accounts payable - trade | 
                                                187,263,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                196,917,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accounts payable - other | 
                                                249,802,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                254,281,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current portion of long-term borrowings | 
                                                353,455,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                391,395,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Income taxes payable | 
                                                112,656,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                39,099,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                5,300,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,077,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                147,336,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                104,510,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                1,156,863,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,097,331,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Provisions | ||
| Provision for bonuses | 
                                                1,048,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,048,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Long-term borrowings | 
                                                1,509,059,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,313,878,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | 
                                                1,801,533,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,591,196,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax liabilities | 
                                                49,108,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                53,669,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                31,866,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,779,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                211,498,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                204,869,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                2,958,396,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,688,527,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other liabilities | — | — | 
| Other liabilities | — | — | 
| Liabilities and net assets | ||
| Shareholders' equity | 
                                                1,766,949,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,518,329,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share capital | 
                                                530,450,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                530,450,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | 
                                                440,134,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                439,207,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                842,449,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                603,129,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Treasury shares | 
                                                -46,085,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -54,458,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | 
                                                18,669,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,393,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share acquisition rights | 
                                                50,822,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                57,873,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                1,836,441,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,582,596,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                4,794,838,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,271,124,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | ||
| Shareholders' equity | ||
| Capital surplus | ||
| Retained earnings | ||
| Valuation and translation adjustments |