Quarterly Statement Of Cash Flows
| Concept | 2024-04-01 to 2025-03-31 | As at 2025-03-31 | As at 2024-03-31 | 2023-04-01 to 2024-03-31 | As at 2023-03-31 | 
|---|---|---|---|---|---|
| Quarterly statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Profit (loss) before income taxes | 
                                                -32,381,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -139,629,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Depreciation | 
                                                88,589,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                93,845,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Impairment losses | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                89,619,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Increase (decrease) in allowance for doubtful accounts | 
                                                -42,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                55,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest expenses | 
                                                5,441,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,350,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Decrease (increase) in trade receivables | 
                                                23,596,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -8,796,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Decrease (increase) in inventories | 
                                                -177,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                13,910,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Increase (decrease) in trade payables | 
                                                15,190,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -12,340,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | 
                                                28,308,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                21,530,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Subtotal | 
                                                2,271,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                56,876,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest paid | 
                                                -6,229,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -2,544,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Income taxes paid | 
                                                -31,922,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -36,512,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | 
                                                -67,111,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -25,414,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | 
                                                -197,722,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -85,210,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from sale of property, plant and equipment | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                40,453,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | 
                                                -5,145,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -5,324,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | 
                                                -167,199,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -14,346,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from financing activities | |||||
| Proceeds from short-term borrowings | 
                                                44,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                44,500,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Repayments of short-term borrowings | 
                                                -70,341,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -70,657,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from long-term borrowings | 
                                                145,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Repayments of long-term borrowings | 
                                                -67,344,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -43,141,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from issuance of bonds | 
                                                80,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Redemption of bonds | 
                                                -24,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | 
                                                134,380,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -69,391,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Effect of exchange rate change on cash and cash equivalents | 
                                                -14,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | 
                                                -99,944,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -109,152,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | 
                                                166,232,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                266,177,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                375,329,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |