Statement Of Cash Flows
| Concept | 2024-04-01 to 2025-03-31 | As at 2025-03-31 | As at 2024-03-31 | 2023-04-01 to 2024-03-31 | As at 2023-03-31 | 
|---|---|---|---|---|---|
| Statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Subtotal | 
                                                1,005,737,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                731,911,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest and dividends received | 
                                                8,036,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                6,977,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest paid | 
                                                -6,471,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -6,919,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Income taxes paid | 
                                                -302,520,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -301,391,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from operating activities | |||||
| Net cash provided by (used in) operating activities | 
                                                704,782,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                430,578,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from operating activities | |||||
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | 
                                                -71,486,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -73,707,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from sale of property, plant and equipment | 
                                                4,180,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                5,126,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | 
                                                -71,304,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -72,828,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | 
                                                1,451,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -2,247,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from facilities maintenance and investing activities | |||||
| Cash flows from financing activities | |||||
| Dividends paid | 
                                                -142,204,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -111,173,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from long-term borrowings | 
                                                300,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                150,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | 
                                                -411,037,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -203,726,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Repayments of long-term borrowings | 
                                                -300,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -200,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Effect of exchange rate change on cash and cash equivalents | 
                                                -1,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                12,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | 
                                                222,439,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                154,035,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | 
                                                3,056,322,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,833,883,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,679,848,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |