Consolidated Statement Of Cash Flows
| Concept | As at 2023-03-31 | 2022-04-01 to 2023-03-31 | As at 2022-03-31 | 2021-04-01 to 2022-03-31 | As at 2021-03-31 | 
|---|---|---|---|---|---|
| Consolidated statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Subtotal | — | 
                                                -562,409,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -474,968,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Income taxes paid | — | 
                                                -1,927,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -1,927,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                -564,274,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -476,842,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | — | 
                                                -163,870,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -33,868,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | 
                                                -212,989,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -33,868,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from financing activities | |||||
| Proceeds from issuance of shares | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,623,975,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Purchase of treasury shares | — | 
                                                -20,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -20,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,647,548,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -4,868,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Effect of exchange rate change on cash and cash equivalents | — | 
                                                7,365,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                8,714,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                -769,918,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,145,552,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | 
                                                2,444,934,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,214,852,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,069,300,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |