Consolidated Statement Of Cash Flows
| Concept | As at 2024-12-31 | 2024-01-01 to 2024-12-31 | 2023-01-01 to 2023-12-31 | As at 2023-12-31 | As at 2022-12-31 | 
|---|---|---|---|---|---|
| Consolidated statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Subtotal | — | 
                                                -794,017,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -678,354,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | — | 
                                                -2,542,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,441,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest paid | — | 
                                                -9,941,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -9,735,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | 
                                                -760,553,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -562,296,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | — | 
                                                -7,612,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -19,474,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) investing activities | — | 
                                                -8,637,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -19,474,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from financing activities | |||||
| Proceeds from issuance of shares | — | 
                                                16,190,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                22,880,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Repayments of long-term borrowings | — | 
                                                -18,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -77,824,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -52,012,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,236,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                -821,203,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -563,534,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | 
                                                2,052,570,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,873,773,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,437,307,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |