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 | 
|---|---|---|---|---|---|
| Statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Profit (loss) before income taxes | 
                                                -1,718,662,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,426,891,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Depreciation | 
                                                1,588,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,512,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Foreign exchange losses (gains) | 
                                                145,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,065,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Subtotal | 
                                                -1,832,363,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,277,127,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | 
                                                -2,609,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                7,044,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | 
                                                -1,834,577,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,279,615,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from operating activities | |||||
| Increase (decrease) in accounts payable - other | 
                                                -82,482,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                117,204,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from operating activities | |||||
| Cash flows from facilities maintenance and investing activities | |||||
| Purchase of property, plant and equipment | 
                                                -116,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,132,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from investing activities | |||||
| Net cash provided by (used in) investing activities | 
                                                -206,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                207,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from financing activities | |||||
| Net cash provided by (used in) financing activities | 
                                                756,696,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,853,195,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Effect of exchange rate change on cash and cash equivalents | 
                                                -145,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,065,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | 
                                                -1,078,232,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                572,721,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | 
                                                338,829,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,417,062,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                844,341,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |