Balance Sheet
| Concept | As at 2025-03-31 | As at 2024-09-30 | 
|---|---|---|
| Balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Current assets | ||
| Cash and deposits | 
                                                13,111,305,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                12,361,726,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Costs on construction contracts in progress | 
                                                2,836,469,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,844,504,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Merchandise | 
                                                1,214,345,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,037,875,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -16,563,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -18,630,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                1,617,839,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,654,789,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                33,694,277,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                32,457,597,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                13,751,864,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                12,503,953,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Property, plant and equipment | 
                                                6,682,041,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,595,368,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Land | 
                                                5,145,617,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,145,617,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Leased assets, net | 
                                                72,119,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                69,019,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Construction in progress | 
                                                79,159,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | 
                                                375,843,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                429,886,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Goodwill | 
                                                242,793,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                278,416,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                133,050,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                151,469,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other assets | — | — | 
| Investment securities | 
                                                1,779,054,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,222,055,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Long-term loans receivable | 
                                                5,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax assets | 
                                                240,271,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                336,576,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -142,255,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -123,953,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | 
                                                6,693,979,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,478,697,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                3,901,754,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,144,721,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Property, plant and equipment | ||
| Own-used assets | ||
| Leased assets | — | — | 
| Tools, furniture and fixtures | — | — | 
| Tools, furniture and fixtures, net | 
                                                105,026,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                89,032,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | ||
| Other intangible assets | ||
| Investments and other assets | ||
| Other assets | ||
| Assets | 
                                                47,446,142,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                44,961,550,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | ||
| Non-current liabilities | 
                                                1,612,285,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,590,496,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Long-term borrowings | 
                                                108,750,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                116,250,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax liabilities | 
                                                184,839,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                163,399,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                777,701,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                769,187,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Lease liabilities | 
                                                52,480,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                50,377,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                20,128,382,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,507,721,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Short-term borrowings | 
                                                1,265,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                230,955,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Income taxes payable | 
                                                551,414,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                356,269,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                2,232,736,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,270,283,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                21,740,667,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                20,098,217,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | 
                                                25,087,429,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                24,193,002,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share capital | 
                                                896,350,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                896,350,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | 
                                                1,404,916,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,360,916,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                22,799,393,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                21,969,467,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Treasury shares | 
                                                -13,230,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -33,730,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | 
                                                618,045,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                670,329,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation difference on available-for-sale securities | 
                                                275,898,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                304,417,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                25,705,474,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                24,863,332,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                47,446,142,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                44,961,550,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | ||
| Lease liabilities | 
                                                26,553,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                25,199,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Advances received on construction contracts in progress | 
                                                1,125,880,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,378,213,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Other liabilities | — | — | 
| Other liabilities | — | — | 
| Net assets | ||
| Shareholders' equity | ||
| Capital surplus | ||
| Retained earnings | ||
| Valuation and translation adjustments |