Consolidated Statement Of Cash Flows
| Concept | As at 2025-03-31 | 2024-04-01 to 2025-03-31 | 2023-04-01 to 2024-03-31 | As at 2024-03-31 | As at 2023-03-31 | 
|---|---|---|---|---|---|
| Consolidated statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Subtotal | — | 
                                                9,594,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                162,699,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | — | 
                                                -7,208,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -7,169,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | 
                                                2,876,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                156,768,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from investing activities | |||||
| Purchase of securities | — | 
                                                -214,777,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -217,173,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from sale of securities | — | 
                                                234,332,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                205,657,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Purchase of property, plant and equipment | — | 
                                                -2,076,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,082,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from sale of property, plant and equipment | — | 
                                                106,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                133,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) investing activities | — | 
                                                107,834,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                70,657,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from financing activities | |||||
| Purchase of treasury shares | — | 
                                                -2,757,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,428,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Dividends paid | — | 
                                                -6,155,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -5,115,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Purchase of shares of subsidiaries not resulting in change in scope of consolidation | — | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -8,912,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -6,543,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Effect of exchange rate change on cash and cash equivalents | — | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                101,797,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                220,890,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | 
                                                1,070,066,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                968,268,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                747,378,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |