Semi-Annual Balance Sheet
| Concept | As at 2024-06-30 | As at 2023-12-31 | 
|---|---|---|
| Semi-annual balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Current assets | ||
| Cash and deposits | 
                                                4,947,268,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,555,691,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                1,395,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,561,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                5,061,786,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,717,089,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Prepaid expenses | 
                                                23,753,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                38,622,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Investments and other assets | ||
| Investments and other assets | 
                                                26,037,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                61,857,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Long-term prepaid expenses | 
                                                2,471,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,699,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                26,037,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                61,857,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Assets | 
                                                5,087,823,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,778,946,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | ||
| Income taxes payable | 
                                                22,399,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                30,210,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                76,058,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                86,260,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accounts payable - other | 
                                                17,284,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,715,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Non-current liabilities | 
                                                5,233,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,233,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                5,233,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,233,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                81,292,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                91,494,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other liabilities | — | — | 
| Other liabilities | — | — | 
| Net assets | ||
| Share capital | 
                                                4,047,254,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,045,977,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | ||
| Capital surplus | ||
| Capital surplus | 
                                                4,025,098,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,023,821,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | ||
| Retained earnings | 
                                                -3,072,668,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,389,247,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | 
                                                4,999,683,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,680,550,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                5,006,531,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,687,452,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share acquisition rights | 
                                                6,847,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,901,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                5,087,823,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,778,946,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |