Quarterly Statement Of Cash Flows
| Concept | 2023-04-01 to 2023-09-30 | As at 2023-09-30 | As at 2023-03-31 | 2022-04-01 to 2022-09-30 | As at 2022-09-30 | As at 2022-03-31 | 
|---|---|---|---|---|---|---|
| Quarterly statement of cash flows | ||||||
| Statement of cash flows | ||||||
| Cash flows from operating activities | ||||||
| Profit (loss) before income taxes | 
                                                -403,626,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                107,001,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Depreciation | 
                                                17,506,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                17,336,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest expenses | 
                                                345,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                421,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Decrease (increase) in trade receivables | 
                                                16,928,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,806,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Decrease (increase) in inventories | 
                                                -16,067,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                41,745,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Increase (decrease) in trade payables | 
                                                -3,041,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,184,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Other, net | 
                                                4,537,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                6,614,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Subtotal | 
                                                -514,337,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                127,997,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest paid | 
                                                -306,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -413,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | 
                                                -41,587,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -21,135,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | 
                                                -551,517,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                108,799,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from investing activities | ||||||
| Purchase of property, plant and equipment | 
                                                -9,242,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -12,343,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) investing activities | 
                                                -9,242,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -23,148,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from financing activities | ||||||
| Repayments of long-term borrowings | 
                                                -10,200,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -72,240,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from issuance of shares | 
                                                53,176,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,074,540,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | 
                                                42,976,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                989,025,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | 
                                                -517,783,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,074,677,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | — | 
                                                1,643,233,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,161,016,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,249,606,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,174,929,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |