Consolidated Balance Sheet
| Concept | As at 2024-03-31 | As at 2023-12-31 | 
|---|---|---|
| Consolidated balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Non-current assets | ||
| Property, plant and equipment | ||
| Property, plant and equipment | 
                                                35,354,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,957,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | 
                                                302,008,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                312,007,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Software | 
                                                43,796,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                45,954,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Goodwill | 
                                                249,912,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                263,796,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | ||
| Other intangible assets | ||
| Investments and other assets | ||
| Investment securities | 
                                                86,343,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                87,204,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax assets | 
                                                151,278,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                148,580,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                76,695,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                77,680,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | 
                                                316,343,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                315,708,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Long-term prepaid expenses | 
                                                2,026,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,242,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                653,706,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                646,673,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | ||
| Cash and deposits | 
                                                1,642,378,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,738,947,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Supplies | 
                                                149,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                149,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                106,929,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                72,822,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Advance payments to suppliers | 
                                                162,801,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                159,075,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -960,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -902,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                2,460,838,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,572,349,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred assets | ||
| Deferred assets | 
                                                4,794,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,495,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share issuance costs | 
                                                3,367,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,943,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Bond issuance costs | 
                                                1,426,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,552,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Assets | 
                                                3,119,339,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,224,518,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | ||
| Non-current liabilities | 
                                                606,275,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                679,092,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Bonds payable | 
                                                80,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                100,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Long-term borrowings | 
                                                526,275,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                579,092,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                1,154,016,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,167,342,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accounts payable - other | 
                                                112,814,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                156,827,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accrued expenses | 
                                                111,760,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                99,095,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                1,760,291,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,846,434,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | 
                                                1,358,655,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,377,860,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share capital | 
                                                370,665,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                370,618,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | 
                                                360,559,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                360,519,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                627,431,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                646,721,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share acquisition rights | 
                                                392,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                224,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                1,359,048,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,378,084,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                3,119,339,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,224,518,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Non-current liabilities | ||
| Current liabilities | ||
| Current portion of long-term borrowings | 
                                                216,173,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                225,347,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current portion of bonds payable | 
                                                40,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                40,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                47,339,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                33,756,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | ||
| Shareholders' equity |