Statement Of Cash Flows
| Concept | As at 2023-03-31 | 2022-04-01 to 2023-03-31 | 2022-04-01 to 2023-03-31 | 2021-04-01 to 2022-03-31 | As at 2022-03-31 | 2021-04-01 to 2022-03-31 | As at 2021-03-31 | 
|---|---|---|---|---|---|---|---|
| Statement of cash flows | |||||||
| Statement of cash flows | |||||||
| Cash flows from operating activities | |||||||
| Profit (loss) before income taxes | — | 
                                                672,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,221,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,627,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                708,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Depreciation | — | — | 
                                                1,991,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,068,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Impairment losses | — | — | 
                                                744,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                763,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Increase (decrease) in allowance for doubtful accounts | — | — | 
                                                87,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Interest and dividend income | — | — | 
                                                -200,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -161,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Interest expenses | — | — | 
                                                80,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                114,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Foreign exchange losses (gains) | — | — | 
                                                -180,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -176,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Increase (decrease) in provision for bonuses | — | — | 
                                                21,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                23,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Decrease (increase) in trade receivables | — | — | 
                                                2,906,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                146,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Decrease (increase) in inventories | — | — | 
                                                -278,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,088,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Subtotal | — | — | 
                                                4,455,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,995,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Increase (decrease) in trade payables | — | — | 
                                                -1,837,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,146,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Income taxes paid | — | — | 
                                                -981,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -758,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Other, net | — | — | 
                                                -90,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,147,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Net cash provided by (used in) operating activities | — | — | 
                                                3,606,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,297,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Interest and dividends received | — | — | 
                                                212,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                174,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Interest paid | — | — | 
                                                -79,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -114,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Cash flows from operating activities | |||||||
| Loss (gain) on sale of investment securities | — | — | 
                                                -75,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                36,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Cash flows from operating activities | |||||||
| Cash flows from investing activities | |||||||
| Purchase of property, plant and equipment | — | — | 
                                                -2,143,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,541,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Proceeds from sale of property, plant and equipment | — | — | 
                                                64,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Purchase of investment securities | — | — | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Net cash provided by (used in) investing activities | — | — | 
                                                -2,147,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,360,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Proceeds from sale of investment securities | — | — | 
                                                439,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                118,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Loan advances | — | — | 
                                                -1,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -4,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Proceeds from collection of loans receivable | — | — | 
                                                3,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Other, net | — | — | 
                                                -38,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -52,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Cash flows from facilities maintenance and investing activities | |||||||
| Cash flows from financing activities | |||||||
| Proceeds from long-term borrowings | — | — | 
                                                1,100,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,900,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Dividends paid | — | — | 
                                                -563,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -580,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Repayments of long-term borrowings | — | — | 
                                                -4,027,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,623,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Net cash provided by (used in) financing activities | — | — | 
                                                -3,215,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -4,210,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Other, net | — | — | 
                                                -68,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -54,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Net increase (decrease) in cash and cash equivalents | — | — | 
                                                -1,016,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,563,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Effect of exchange rate change on cash and cash equivalents | — | — | 
                                                740,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                709,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Cash and cash equivalents | 
                                                9,821,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                10,838,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                12,402,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |