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 | — | 
                                                5,257,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,708,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest and dividends received | — | 
                                                223,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                170,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Income taxes paid | — | 
                                                -1,028,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -260,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Interest paid | — | 
                                                -271,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -200,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) operating activities | — | 
                                                4,213,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,941,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from operating activities | |||||
| Cash flows from operating activities | |||||
| Cash flows from facilities maintenance and investing activities | |||||
| Purchase of property, plant and equipment | — | 
                                                -1,489,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,736,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Other, net | — | 
                                                35,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from investing activities | |||||
| Net cash provided by (used in) investing activities | — | 
                                                -10,759,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,254,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash flows from financing activities | |||||
| Proceeds from short-term borrowings | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,400,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Purchase of treasury shares | — | 
                                                -4,812,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Repayments of short-term borrowings | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,200,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Dividends paid | — | 
                                                -679,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -713,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Proceeds from long-term borrowings | — | 
                                                9,500,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,523,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Repayments of long-term borrowings | — | 
                                                -5,650,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -5,643,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net cash provided by (used in) financing activities | — | 
                                                -251,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,252,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Effect of exchange rate change on cash and cash equivalents | — | 
                                                110,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                49,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Net increase (decrease) in cash and cash equivalents | — | 
                                                -6,686,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,988,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
| Cash and cash equivalents | 
                                                13,708,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                20,394,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                14,405,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |