Statement Of Cash Flows
| Concept | As at 2023-09-30 | 2023-04-01 to 2023-09-30 | As at 2023-03-31 | As at 2022-09-30 | 2022-04-01 to 2022-09-30 | As at 2022-03-31 | 
|---|---|---|---|---|---|---|
| Statement of cash flows | ||||||
| Statement of cash flows | ||||||
| Cash flows from operating activities | ||||||
| Subtotal | — | 
                                                1,661,149,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                784,095,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest and dividends received | — | 
                                                516,012,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                194,922,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Interest paid | — | 
                                                -14,351,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -7,971,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Income taxes paid | — | 
                                                -664,999,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -645,470,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from operating activities | ||||||
| Net cash provided by (used in) operating activities | — | 
                                                1,497,811,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                325,574,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from operating activities | ||||||
| Cash flows from investing activities | ||||||
| Purchase of property, plant and equipment | — | 
                                                -559,288,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -419,515,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from sale of property, plant and equipment | — | 
                                                281,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                81,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) investing activities | — | 
                                                -1,887,382,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -207,398,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Purchase of investment securities | — | 
                                                -2,990,146,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -7,013,779,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Other, net | — | 
                                                3,155,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                31,188,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash flows from facilities maintenance and investing activities | ||||||
| Cash flows from financing activities | ||||||
| Dividends paid | — | 
                                                -464,925,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                -464,925,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Proceeds from long-term borrowings | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                500,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -464,925,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                35,074,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                -791,562,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                277,361,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Effect of exchange rate change on cash and cash equivalents | — | 
                                                62,934,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                124,111,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Cash and cash equivalents | 
                                                19,185,110,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                19,976,673,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,316,569,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                18,039,208,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |