Semi-Annual Consolidated Balance Sheet
| Concept | As at 2023-09-30 | As at 2023-03-31 | 
|---|---|---|
| Semi-annual consolidated balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Current assets | ||
| Cash and deposits | 
                                                5,803,921,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,941,896,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Inventories | 
                                                3,838,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,738,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                23,413,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                28,191,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                5,831,619,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,977,402,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Property, plant and equipment | 
                                                530,748,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                562,147,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Property, plant and equipment | ||
| Other | — | — | 
| Other, net | 
                                                118,470,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                132,022,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | ||
| Intangible assets | 
                                                6,629,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,500,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | 
                                                41,577,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                42,368,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | ||
| Non-current assets | 
                                                578,954,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                610,015,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Assets | 
                                                6,410,574,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,587,417,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | ||
| Income taxes payable | 
                                                22,757,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,850,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                188,711,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                97,425,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Asset retirement obligations | 
                                                28,401,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                28,365,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | 
                                                35,197,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                36,369,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                223,909,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                133,794,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax liabilities | 
                                                6,796,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,003,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | ||
| Shareholders' equity | ||
| Share capital | 
                                                1,543,610,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | 
                                                6,442,355,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,908,744,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                -1,797,530,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,469,955,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Treasury shares | 
                                                -11,836,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -11,748,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | 
                                                6,176,598,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,437,041,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share acquisition rights | 
                                                10,066,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                16,582,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                6,186,665,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,453,623,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                6,410,574,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,587,417,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |