Quarterly Consolidated 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 | 
|---|---|---|---|---|---|
| Quarterly consolidated statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Profit (loss) before income taxes | 
                                                49,216,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                99,016,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Depreciation | 
                                                133,154,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                133,568,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Impairment losses | 
                                                4,921,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Increase (decrease) in allowance for doubtful accounts | 
                                                -311,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -311,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest and dividend income | 
                                                -135,974,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -120,906,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Decrease (increase) in trade receivables | 
                                                355,415,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                364,384,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Decrease (increase) in inventories | 
                                                59,853,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -90,381,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Increase (decrease) in trade payables | 
                                                -426,991,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,488,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | 
                                                -4,426,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                8,245,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Subtotal | 
                                                -103,384,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                266,582,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest and dividends received | 
                                                135,879,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                120,888,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | 
                                                54,769,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                302,832,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | 
                                                -75,730,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -82,879,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Purchase of investment securities | 
                                                -91,513,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from sale of investment securities | 
                                                149,639,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | 
                                                -163,178,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -81,129,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from financing activities | |||||
| Purchase of treasury shares | 
                                                -9,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -38,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Dividends paid | 
                                                -83,259,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -83,239,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | 
                                                -83,268,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -83,277,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Effect of exchange rate change on cash and cash equivalents | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | 
                                                -191,678,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                138,425,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | 
                                                1,880,895,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,072,573,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,934,148,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |