Consolidated Statement Of Cash Flows
| Concept | 2023-04-01 to 2024-03-31 | As at 2024-03-31 | As at 2023-03-31 | 2022-04-01 to 2023-03-31 | As at 2022-03-31 | 
|---|---|---|---|---|---|
| Consolidated statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Subtotal | 
                                                3,562,341,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,245,272,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest and dividends received | 
                                                24,643,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                21,823,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest paid | 
                                                -109,609,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -120,983,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Income taxes paid | 
                                                -79,715,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,107,720,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | 
                                                3,727,246,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,075,913,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | 
                                                -2,116,578,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -1,741,537,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from sale of property, plant and equipment | 
                                                43,149,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,081,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | 
                                                -2,292,734,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -2,801,759,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Purchase of shares of subsidiaries resulting in change in scope of consolidation | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -830,687,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | 
                                                -23,221,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -54,959,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from financing activities | |||||
| Dividends paid | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -199,359,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from long-term borrowings | 
                                                1,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,019,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Redemption of bonds | 
                                                -935,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -935,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Repayments of long-term borrowings | 
                                                -1,087,921,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -949,541,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | 
                                                -1,216,062,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -30,998,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | 
                                                98,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Effect of exchange rate change on cash and cash equivalents | 
                                                2,724,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                743,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | 
                                                221,174,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -756,101,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | 
                                                12,371,553,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                12,150,379,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                12,834,637,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |