Consolidated Statement Of Cash Flows
| Concept | As at 2024-09-30 | 2024-04-01 to 2024-09-30 | As at 2024-03-31 | As at 2023-09-30 | 2023-04-01 to 2023-09-30 | As at 2023-03-31 | 
|---|---|---|---|---|---|---|
| Consolidated statement of cash flows | ||||||
| Statement of cash flows | ||||||
| Cash flows from operating activities | ||||||
| Subtotal | — | 
                                                601,010,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                509,591,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest and dividends received | — | 
                                                4,866,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,998,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest paid | — | 
                                                -52,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -135,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                565,253,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                519,627,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from investing activities | ||||||
| Purchase of property, plant and equipment | — | 
                                                -192,793,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -180,475,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | 
                                                -238,616,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -183,338,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from financing activities | ||||||
| Purchase of treasury shares | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -245,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Dividends paid | — | 
                                                -260,726,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -231,766,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -262,623,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -233,620,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Effect of exchange rate change on cash and cash equivalents | — | 
                                                3,528,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                8,014,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                67,541,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                110,683,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | 
                                                2,790,918,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,723,377,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,261,164,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,150,481,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |