Statement Of Cash Flows
| Concept | As at 2025-03-31 | 2024-04-01 to 2025-03-31 | 2023-04-01 to 2024-03-31 | As at 2024-03-31 | As at 2023-03-31 | 
|---|---|---|---|---|---|
| Statement of cash flows | |||||
| Statement of cash flows | |||||
| Cash flows from operating activities | |||||
| Subtotal | — | 
                                                5,718,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,887,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest and dividends received | — | 
                                                366,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                290,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest paid | — | 
                                                -124,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -86,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | — | 
                                                -903,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,112,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | 
                                                5,056,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,978,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from operating activities | |||||
| Cash flows from operating activities | |||||
| Cash flows from investing activities | |||||
| Purchase of property, plant and equipment | — | 
                                                -7,334,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,617,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from sale of property, plant and equipment | — | 
                                                103,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                48,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Purchase of investment securities | — | 
                                                -7,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -7,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) investing activities | — | 
                                                -7,077,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,949,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from sale of investment securities | — | 
                                                97,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                31,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Other, net | — | 
                                                -148,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -588,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from facilities maintenance and investing activities | |||||
| Cash flows from financing activities | |||||
| Purchase of treasury shares | — | 
                                                -314,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -252,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Dividends paid | — | 
                                                -875,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -832,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from long-term borrowings | — | 
                                                6,500,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,155,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Repayments of long-term borrowings | — | 
                                                -3,484,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,214,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | — | 
                                                1,678,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,453,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Other, net | — | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -31,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                -215,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,647,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Effect of exchange rate change on cash and cash equivalents | — | 
                                                126,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                163,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | 
                                                14,013,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                14,229,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                11,582,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |