Statement Of Cash Flows
| Concept | As at 2024-06-30 | 2024-01-01 to 2024-06-30 | As at 2023-12-31 | As at 2023-06-30 | 2023-01-01 to 2023-06-30 | As at 2022-12-31 | 
|---|---|---|---|---|---|---|
| Statement of cash flows | ||||||
| Statement of cash flows | ||||||
| Cash flows from operating activities | ||||||
| Profit (loss) before income taxes | — | 
                                                76,682,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                280,736,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Depreciation | — | 
                                                178,483,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                127,715,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Increase (decrease) in allowance for doubtful accounts | — | 
                                                -245,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -128,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest and dividend income | — | 
                                                -2,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -2,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest expenses | — | 
                                                5,628,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                5,938,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Increase (decrease) in provision for bonuses | — | 
                                                514,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                5,523,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Decrease (increase) in trade receivables | — | 
                                                373,313,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                193,967,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Decrease (increase) in inventories | — | 
                                                29,835,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                24,312,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Increase (decrease) in trade payables | — | 
                                                -3,008,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -11,824,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Subtotal | — | 
                                                734,699,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                479,505,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | — | 
                                                -2,220,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -23,380,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Income taxes paid | — | 
                                                -82,106,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -128,499,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                649,668,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                344,391,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest and dividends received | — | 
                                                2,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest paid | — | 
                                                -6,226,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -6,616,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from operating activities | ||||||
| Loss (gain) on sale of non-current assets | — | 
                                                -499,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,908,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from operating activities | ||||||
| Cash flows from facilities maintenance and investing activities | ||||||
| Purchase of property, plant and equipment | — | 
                                                -57,424,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -587,532,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from sale of property, plant and equipment | — | 
                                                500,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,204,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from investing activities | ||||||
| Net cash provided by (used in) investing activities | — | 
                                                -65,922,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -602,378,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from financing activities | ||||||
| Proceeds from issuance of shares | — | 
                                                12,400,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from long-term borrowings | — | 
                                                100,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                550,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Repayments of long-term borrowings | — | 
                                                -143,006,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -120,842,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -118,700,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                368,561,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                465,045,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                110,573,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | 
                                                768,289,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                303,243,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                417,134,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                306,561,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |