Quarterly Statement Of Cash Flows
| Concept | As at 2024-09-30 | 2024-04-01 to 2024-09-30 | As at 2024-03-31 | As at 2023-09-30 | 2023-04-01 to 2023-09-30 | As at 2023-03-31 | 
|---|---|---|---|---|---|---|
| Quarterly statement of cash flows | ||||||
| Statement of cash flows | ||||||
| Cash flows from operating activities | ||||||
| Subtotal | — | 
                                                535,083,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                618,104,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest and dividends received | — | 
                                                2,316,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                895,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest paid | — | 
                                                -1,402,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -2,038,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | — | 
                                                381,608,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                606,001,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from investing activities | ||||||
| Purchase of property, plant and equipment | — | 
                                                -642,144,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -62,805,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from sale of property, plant and equipment | — | 
                                                11,555,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                136,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | — | 
                                                -2,613,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                39,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | 
                                                -642,120,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -131,262,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from financing activities | ||||||
| Repayments of long-term borrowings | — | 
                                                -114,832,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -134,932,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Dividends paid | — | 
                                                -405,111,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -326,146,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -523,019,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -464,127,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Effect of exchange rate change on cash and cash equivalents | — | 
                                                7,657,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                2,653,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                -775,873,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                13,265,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | 
                                                3,073,047,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                3,848,921,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,243,955,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                4,230,689,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |