Quarterly Statement Of Cash Flows
| Concept | 2024-04-01 to 2024-09-30 | As at 2024-09-30 | As at 2024-03-31 | 2023-04-01 to 2023-09-30 | As at 2023-09-30 | As at 2023-03-31 | 
|---|---|---|---|---|---|---|
| Quarterly statement of cash flows | ||||||
| Statement of cash flows | ||||||
| Cash flows from operating activities | ||||||
| Profit (loss) before income taxes | 
                                                474,457,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                528,417,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Depreciation | 
                                                50,398,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                57,452,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Decrease (increase) in trade receivables | 
                                                6,839,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -228,537,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Decrease (increase) in inventories | 
                                                27,535,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -33,546,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Increase (decrease) in trade payables | 
                                                -48,155,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                35,691,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Other, net | 
                                                27,225,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -34,137,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Subtotal | 
                                                498,445,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                171,862,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest and dividends received | 
                                                4,154,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                3,814,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest paid | 
                                                -3,620,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -3,380,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | 
                                                -153,136,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -155,779,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | 
                                                345,843,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                16,516,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from investing activities | ||||||
| Purchase of property, plant and equipment | 
                                                -16,177,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -64,053,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from sale of property, plant and equipment | 
                                                4,180,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Other, net | 
                                                -197,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -320,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) investing activities | 
                                                -12,194,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -66,374,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from financing activities | ||||||
| Proceeds from long-term borrowings | 
                                                200,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                150,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Repayments of long-term borrowings | 
                                                -200,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -200,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Dividends paid | 
                                                -142,082,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -111,080,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Other, net | 
                                                -14,487,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -21,169,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | 
                                                -396,569,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -182,250,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Effect of exchange rate change on cash and cash equivalents | 
                                                -254,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                1,223,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | 
                                                -63,175,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -230,884,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | — | 
                                                2,770,707,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,833,883,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                2,448,963,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,679,848,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |