Consolidated Statement Of Cash Flows
| Concept | As at 2025-03-20 | 2024-03-21 to 2025-03-20 | 2023-03-21 to 2024-03-20 | As at 2024-03-20 | As at 2023-03-20 | 
|---|---|---|---|---|---|
| Consolidated statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Subtotal | — | 
                                                425,063,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                468,368,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest and dividends received | — | 
                                                94,702,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                65,007,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest paid | — | 
                                                -5,713,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,459,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | — | 
                                                -96,341,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -34,281,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | 
                                                418,599,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                499,535,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | — | 
                                                -663,548,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -234,204,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from sale of property, plant and equipment | — | 
                                                13,791,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,413,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) investing activities | — | 
                                                -703,346,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -282,802,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from financing activities | |||||
| Purchase of treasury shares | — | 
                                                -158,654,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -925,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Dividends paid | — | 
                                                -59,628,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -59,696,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from long-term borrowings | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                700,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Repayments of long-term borrowings | — | 
                                                -250,072,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -110,084,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -317,488,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                526,014,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Effect of exchange rate change on cash and cash equivalents | — | 
                                                34,100,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                16,649,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                -568,134,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                759,396,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | 
                                                1,009,636,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,577,771,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                818,374,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |