Consolidated Balance Sheet
| Concept | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2022-03-31 | As at 2022-03-31 | As at 2022-03-31 | As at 2022-03-31 | As at 2022-03-31 | As at 2022-03-31 | As at 2022-03-31 | As at 2022-03-31 | As at 2022-03-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Consolidated balance sheet | |||||||||||||||||||||||||||
| Balance sheet | |||||||||||||||||||||||||||
| Assets | |||||||||||||||||||||||||||
| Current assets | |||||||||||||||||||||||||||
| Cash and deposits | — | — | — | — | — | — | — | 
                                                2,231,411,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,067,162,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Accounts receivable - trade | — | — | — | — | — | — | — | 
                                                881,407,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,036,216,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Contract assets | — | — | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                52,550,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Prepaid expenses | — | — | — | — | — | — | — | 
                                                7,930,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                11,957,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Work in process | — | — | — | — | — | — | — | 
                                                875,654,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                422,308,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Advance payments to suppliers | — | — | — | — | — | — | — | 
                                                739,567,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                821,536,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Other | — | — | — | — | — | — | — | 
                                                188,251,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                72,416,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Current assets | — | — | — | — | — | — | — | 
                                                4,924,221,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                3,697,155,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Non-current assets | — | — | — | — | — | — | — | 
                                                161,329,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                197,609,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Investments and other assets | — | — | — | — | — | — | — | 
                                                158,478,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                193,836,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Investment securities | — | — | — | — | — | — | — | 
                                                138,218,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                173,218,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Other | — | — | — | — | — | — | — | 
                                                20,259,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                20,618,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Non-current assets | |||||||||||||||||||||||||||
| Property, plant and equipment | — | — | — | — | — | — | — | 
                                                1,320,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,476,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Buildings, net | — | — | — | — | — | — | — | 
                                                1,308,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,438,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Property, plant and equipment | |||||||||||||||||||||||||||
| Intangible assets | |||||||||||||||||||||||||||
| Intangible assets | — | — | — | — | — | — | — | 
                                                1,530,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                2,297,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Software | — | — | — | — | — | — | — | 
                                                650,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,301,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Investments and other assets | |||||||||||||||||||||||||||
| Assets | — | — | — | — | — | — | — | 
                                                5,085,550,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                3,894,765,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Liabilities and net assets | |||||||||||||||||||||||||||
| Non-current liabilities | — | — | — | — | — | — | — | 
                                                1,878,850,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,605,420,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Long-term borrowings | — | — | — | — | — | — | — | 
                                                1,337,960,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,075,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Current liabilities | — | — | — | — | — | — | — | 
                                                2,375,227,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,055,839,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Accounts payable - other | — | — | — | — | — | — | — | 
                                                380,586,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                482,286,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Accrued expenses | — | — | — | — | — | — | — | 
                                                1,326,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,262,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Deposits received | — | — | — | — | — | — | — | 
                                                13,920,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                9,046,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Liabilities | — | — | — | — | — | — | — | 
                                                4,254,077,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                2,661,259,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Shareholders' equity | — | — | — | — | — | — | — | 
                                                669,892,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,037,518,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Share capital | — | — | — | — | — | — | — | 
                                                2,036,724,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                1,509,497,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Capital surplus | — | — | — | — | — | — | — | 
                                                11,342,324,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                10,815,098,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Retained earnings | — | — | — | — | — | — | — | 
                                                -12,709,082,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -11,287,004,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Treasury shares | — | — | — | — | — | — | — | 
                                                -73,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -73,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Share acquisition rights | — | — | — | — | — | — | — | 
                                                161,581,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                195,987,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Net assets | 
                                                669,892,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                11,342,324,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                11,342,324,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -73,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -12,709,082,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                161,581,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,036,724,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                831,473,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -12,709,082,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,509,497,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -11,287,004,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,233,505,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,815,098,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                195,987,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,815,098,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -73,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,037,518,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -11,287,004,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,726,813,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -73,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -10,629,570,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,421,212,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                184,525,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,702,908,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -10,629,570,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,726,813,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,518,382,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | — | — | — | — | — | — | — | 
                                                5,085,550,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                3,894,765,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Liabilities | |||||||||||||||||||||||||||
| Current liabilities | |||||||||||||||||||||||||||
| Income taxes payable | — | — | — | — | — | — | — | 
                                                39,439,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                32,680,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Current portion of long-term borrowings | — | — | — | — | — | — | — | 
                                                737,040,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                375,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Non-current liabilities | |||||||||||||||||||||||||||
| Net assets | |||||||||||||||||||||||||||
| Shareholders' equity |