Quarterly 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 | 
|---|---|---|---|---|---|---|
| Quarterly consolidated statement of cash flows | ||||||
| Statement of cash flows | ||||||
| Cash flows from operating activities | ||||||
| Subtotal | — | 
                                                178,558,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                646,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest and dividends received | — | 
                                                20,590,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                19,330,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Income taxes paid | — | 
                                                -271,402,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -272,371,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                -72,253,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                392,959,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from investing activities | ||||||
| Purchase of property, plant and equipment | — | 
                                                -37,350,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -16,575,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Purchase of investment securities | — | 
                                                -2,010,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | — | 
                                                -950,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -12,548,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | 
                                                -103,138,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -34,585,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from financing activities | ||||||
| Purchase of treasury shares | — | 
                                                -178,594,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Dividends paid | — | 
                                                -223,247,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -186,392,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | — | 
                                                -2,285,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,062,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -404,126,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -187,454,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                -579,518,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                170,919,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | 
                                                3,180,336,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,759,855,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,562,185,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,391,266,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |