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 | — | 
                                                6,791,364,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,008,928,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest and dividends received | — | 
                                                2,474,071,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,447,208,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest paid | — | 
                                                -216,898,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -125,838,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | — | 
                                                -2,013,292,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,223,564,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | 
                                                7,035,243,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,106,732,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | — | 
                                                -10,853,565,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -8,583,031,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from sale of property, plant and equipment | — | 
                                                4,205,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,288,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) investing activities | — | 
                                                -11,691,221,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -6,907,735,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Purchase of investment securities | — | 
                                                -925,974,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -240,367,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from sale of investment securities | — | 
                                                24,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                280,074,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Purchase of shares of subsidiaries resulting in change in scope of consolidation | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -850,364,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Other, net | — | 
                                                8,954,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -50,387,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from financing activities | |||||
| Purchase of treasury shares | — | 
                                                -325,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from long-term borrowings | — | 
                                                14,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                17,700,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Dividends paid | — | 
                                                -2,100,072,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,072,413,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Repayments of long-term borrowings | — | 
                                                -8,826,167,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -6,230,185,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Dividends paid to non-controlling interests | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,950,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | — | 
                                                5,914,147,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,318,656,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Effect of exchange rate change on cash and cash equivalents | — | 
                                                369,805,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                559,424,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                1,627,974,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,077,078,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | 
                                                11,843,986,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                10,274,773,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,197,694,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |