Semi-Annual Consolidated 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 | 
|---|---|---|---|---|---|---|
| Semi-annual consolidated statement of cash flows | ||||||
| Statement of cash flows | ||||||
| Cash flows from operating activities | ||||||
| Subtotal | 
                                                11,983,576,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                9,380,155,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest and dividends received | 
                                                644,471,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                662,620,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | 
                                                -2,218,736,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -2,920,061,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | 
                                                10,409,312,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                7,122,714,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from investing activities | ||||||
| Purchase of property, plant and equipment | 
                                                -39,949,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -81,134,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from sale of investment securities | 
                                                142,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,039,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) investing activities | 
                                                -765,833,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -154,254,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from financing activities | ||||||
| Purchase of treasury shares | 
                                                -445,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -162,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Dividends paid | 
                                                -2,630,760,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -2,630,656,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | 
                                                -2,631,205,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -2,630,818,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | 
                                                7,012,273,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                4,337,640,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | — | 
                                                141,456,507,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                134,444,233,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                128,796,930,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                124,459,289,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |