Quarterly 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 | 
|---|---|---|---|---|---|
| Quarterly statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Subtotal | 
                                                366,210,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                518,867,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest and dividends received | 
                                                4,768,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,907,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest paid | 
                                                -60,227,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -58,939,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Income taxes paid | 
                                                -32,531,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -65,182,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | 
                                                337,820,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                423,634,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | 
                                                -566,166,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -313,813,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from sale of property, plant and equipment | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                10,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Purchase of investment securities | 
                                                -3,297,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -11,630,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from sale of investment securities | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                67,653,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | 
                                                -473,782,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -256,373,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from financing activities | |||||
| Proceeds from long-term borrowings | 
                                                940,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                950,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Repayments of long-term borrowings | 
                                                -872,166,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -982,140,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | 
                                                220,886,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -288,495,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Effect of exchange rate change on cash and cash equivalents | 
                                                48,663,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -4,606,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | 
                                                133,588,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -125,840,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | 
                                                1,665,328,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,531,740,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                1,657,580,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |