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 | 
|---|---|---|---|---|---|
| Statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Profit (loss) before income taxes | — | 
                                                107,112,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                114,118,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Depreciation | — | 
                                                7,366,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,862,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Increase (decrease) in allowance for doubtful accounts | — | 
                                                -4,990,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -831,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest and dividend income | — | 
                                                -1,783,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,710,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest expenses | — | 
                                                14,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                28,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Subtotal | — | 
                                                -65,571,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                381,860,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest and dividends received | — | 
                                                1,783,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,710,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest paid | — | 
                                                -14,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -28,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | — | 
                                                -52,085,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -39,172,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from operating activities | |||||
| Increase (decrease) in provision for retirement benefits | — | 
                                                29,075,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                16,079,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Decrease (increase) in trade receivables | — | 
                                                107,127,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                210,084,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Increase (decrease) in trade payables | — | 
                                                -186,592,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -68,340,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | 
                                                -115,888,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                344,370,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Decrease (increase) in other assets | — | 
                                                6,995,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -5,706,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Increase (decrease) in other liabilities | — | 
                                                -27,308,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                17,094,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from operating activities | |||||
| Cash flows from facilities maintenance and investing activities | |||||
| Purchase of property, plant and equipment | — | 
                                                -3,986,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -839,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Purchase of investment securities | — | 
                                                -202,500,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from investing activities | |||||
| Net cash provided by (used in) investing activities | — | 
                                                -228,276,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -17,623,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from financing activities | |||||
| Proceeds from issuance of shares | — | 
                                                14,476,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,109,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Purchase of treasury shares | — | 
                                                -35,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -17,566,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Dividends paid | — | 
                                                -123,248,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -122,568,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -109,487,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -116,933,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Other, net | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                17,760,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                -453,652,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                209,813,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | 
                                                962,361,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,416,013,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,206,199,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |