Quarterly Consolidated Statement Of Cash Flows
| Concept | 2024-04-01 to 2025-03-31 | As at 2025-03-31 | 2024-04-01 to 2025-03-31 | 2023-04-01 to 2024-03-31 | As at 2024-03-31 | 2023-04-01 to 2024-03-31 | As at 2023-03-31 | 
|---|---|---|---|---|---|---|---|
| Quarterly consolidated statement of cash flows | |||||||
| Statement of cash flows | |||||||
| Cash flows from operating activities | |||||||
| Profit (loss) before income taxes | 
                                                -953,111,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -602,744,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -655,617,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                -544,689,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
| Depreciation | — | — | 
                                                82,568,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                57,729,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Impairment losses | — | — | 
                                                112,324,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                93,782,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Amortization of goodwill | — | — | 
                                                131,384,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                39,233,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Increase (decrease) in allowance for doubtful accounts | — | — | 
                                                -504,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -27,271,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Interest and dividend income | — | — | 
                                                -5,797,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -32,172,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Interest expenses | — | — | 
                                                52,582,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                41,572,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Loss (gain) on sale of property, plant and equipment | — | — | 
                                                -562,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -6,017,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Decrease (increase) in trade receivables | — | — | 
                                                -21,942,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -29,055,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Decrease (increase) in inventories | — | — | 
                                                514,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,891,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Increase (decrease) in trade payables | — | — | 
                                                -24,380,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -32,118,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Other, net | — | — | 
                                                93,462,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                15,799,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Subtotal | — | — | 
                                                -180,435,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -601,417,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Interest and dividends received | — | — | 
                                                12,895,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                39,068,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Interest paid | — | — | 
                                                -45,813,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -41,129,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Income taxes paid | — | — | 
                                                -80,394,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -57,240,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Net cash provided by (used in) operating activities | — | — | 
                                                -293,747,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -632,105,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Cash flows from investing activities | |||||||
| Purchase of property, plant and equipment | — | — | 
                                                -321,334,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -839,456,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Proceeds from sale of property, plant and equipment | — | — | 
                                                725,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,017,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Purchase of shares of subsidiaries resulting in change in scope of consolidation | — | — | 
                                                -170,827,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Other, net | — | — | 
                                                3,970,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,200,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Net cash provided by (used in) investing activities | — | — | 
                                                -395,487,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -759,192,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Cash flows from financing activities | |||||||
| Proceeds from long-term borrowings | — | — | 
                                                750,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Repayments of long-term borrowings | — | — | 
                                                -336,041,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -261,677,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Net cash provided by (used in) financing activities | — | — | 
                                                321,165,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,708,156,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Net increase (decrease) in cash and cash equivalents | — | — | 
                                                -368,070,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                316,858,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
| Cash and cash equivalents | — | 
                                                209,092,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                577,162,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                260,304,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |