Semi-Annual Consolidated Statement Of Cash Flows
| Concept | 2024-01-01 to 2024-12-31 | As at 2024-12-31 | 2023-01-01 to 2023-12-31 | As at 2023-12-31 | As at 2022-12-31 | 
|---|---|---|---|---|---|
| Semi-annual consolidated statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Subtotal | 
                                                236,287,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -272,882,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest and dividends received | 
                                                31,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest paid | 
                                                -6,101,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -5,630,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Compensation paid for damage | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -18,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | 
                                                -32,364,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -48,829,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | 
                                                197,852,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -345,339,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | 
                                                -55,969,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -65,280,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from sale of property, plant and equipment | 
                                                18,031,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                52,101,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) investing activities | 
                                                -192,411,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -26,270,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from financing activities | |||||
| Repayments of short-term borrowings | 
                                                -9,578,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -3,549,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Repayments of long-term borrowings | 
                                                -114,264,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -58,315,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from issuance of shares | 
                                                24,860,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                592,327,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | 
                                                -99,166,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                533,111,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Effect of exchange rate change on cash and cash equivalents | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | 
                                                -93,725,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                161,501,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | — | 
                                                190,414,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                284,139,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                122,638,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |