Quarterly 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 | 
|---|---|---|---|---|---|
| Quarterly consolidated statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Subtotal | — | 
                                                309,826,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                950,208,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest and dividends received | — | 
                                                2,653,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,348,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest paid | — | 
                                                -1,126,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,966,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Compensation paid for damage | — | 
                                                -8,657,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | — | 
                                                -314,725,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -268,298,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | 
                                                -17,385,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                713,930,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | — | 
                                                -69,578,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -72,997,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from sale of property, plant and equipment | — | 
                                                9,824,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,295,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Loan advances | — | 
                                                -21,399,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,778,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from collection of loans receivable | — | 
                                                3,253,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,053,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Other, net | — | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) investing activities | — | 
                                                -49,106,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -41,030,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from financing activities | |||||
| Purchase of treasury shares | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -29,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Dividends paid | — | 
                                                -127,866,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -115,178,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -185,709,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -140,839,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Effect of exchange rate change on cash and cash equivalents | — | 
                                                -2,592,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                19,737,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                -254,794,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                551,797,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | 
                                                5,315,621,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                5,570,415,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,018,617,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |