Statement Of Cash Flows
| Concept | 2024-01-01 to 2024-06-30 | As at 2024-06-30 | As at 2023-12-31 | 2023-01-01 to 2023-06-30 | As at 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 | 
                                                -68,776,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -53,051,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Depreciation | 
                                                132,121,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                117,204,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Increase (decrease) in allowance for doubtful accounts | 
                                                5,028,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                9,431,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest expenses | 
                                                8,726,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                6,022,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Foreign exchange losses (gains) | 
                                                -4,242,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,310,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Increase (decrease) in provision for bonuses | 
                                                3,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Decrease (increase) in trade receivables | 
                                                86,840,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -140,592,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Decrease (increase) in inventories | 
                                                13,584,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -13,024,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Increase (decrease) in trade payables | 
                                                45,978,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -12,338,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Subtotal | 
                                                118,558,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                119,465,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | 
                                                -94,628,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -96,062,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Other, net | 
                                                61,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -211,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | 
                                                -4,833,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                11,831,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest and dividends received | 
                                                16,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                8,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest paid | 
                                                -8,980,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -11,579,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Decrease (increase) in other assets | 
                                                48,355,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                28,588,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Increase (decrease) in other liabilities | 
                                                26,553,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                14,803,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from operating activities | ||||||
| Loss (gain) on sale of investment securities | 
                                                -106,350,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from operating activities | ||||||
| Increase (decrease) in accounts payable - other | 
                                                -127,801,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                170,947,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from facilities maintenance and investing activities | ||||||
| Purchase of property, plant and equipment | 
                                                -1,196,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -284,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Purchase of investment securities | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -29,900,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from sale of investment securities | 
                                                108,199,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from investing activities | ||||||
| Net cash provided by (used in) investing activities | 
                                                80,549,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -91,573,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from financing activities | ||||||
| Proceeds from long-term borrowings | 
                                                49,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Repayments of long-term borrowings | 
                                                -210,271,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -172,366,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | 
                                                -547,386,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                306,405,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Effect of exchange rate change on cash and cash equivalents | 
                                                2,674,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,310,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | 
                                                -468,996,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                227,973,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | — | 
                                                967,027,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,436,023,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,159,894,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                898,182,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |