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 | 
                                                805,844,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                816,704,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest and dividends received | 
                                                17,432,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                17,197,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest paid | 
                                                -14,436,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -15,843,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) operating activities | 
                                                578,611,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                580,086,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | 
                                                -251,090,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -88,637,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from sale of property, plant and equipment | 
                                                88,249,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                22,077,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Purchase of investment securities | 
                                                -534,402,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -799,902,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from collection of loans receivable | 
                                                2,015,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                14,094,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | 
                                                1,662,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -426,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | 
                                                -117,588,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                89,906,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from financing activities | |||||
| Repayments of long-term borrowings | 
                                                -235,006,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -224,891,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Dividends paid | 
                                                -69,927,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -69,197,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | 
                                                -349,513,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -320,696,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Effect of exchange rate change on cash and cash equivalents | 
                                                50,936,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -16,999,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | 
                                                162,445,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                332,297,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | — | 
                                                4,761,467,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,599,022,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                4,266,724,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |