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 | ||
| Buildings, net | 
                                                804,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                817,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Own-used assets | ||
| Land | 
                                                749,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                749,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | — | — | 
| Other, net | 
                                                751,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                684,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Property, plant and equipment | 
                                                2,305,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,251,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | 
                                                11,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                11,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | ||
| Investments and other assets | ||
| Investments and other assets | 
                                                454,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                395,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                2,771,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,658,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | ||
| Cash and deposits | 
                                                9,790,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,134,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accounts receivable - trade | 
                                                3,377,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,755,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Merchandise and finished goods | 
                                                616,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                421,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Work in process | 
                                                366,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                409,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                190,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                159,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -1,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                15,759,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                16,289,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Assets | 
                                                18,530,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,948,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | ||
| Income taxes payable | 
                                                480,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                968,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Provisions | ||
| Provision for bonuses | 
                                                178,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                59,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                934,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                738,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                2,193,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,279,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Provision for retirement benefits for directors (and other officers) | 
                                                738,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                717,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | 
                                                1,023,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                992,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                3,216,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,272,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | ||
| Shareholders' equity | 
                                                15,312,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                15,675,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share capital | 
                                                464,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                464,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | 
                                                274,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                274,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                14,575,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                14,938,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Treasury shares | 
                                                -2,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation difference on available-for-sale securities | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                15,313,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                15,675,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                18,530,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,948,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | ||
| Shareholders' equity | ||
| Valuation and translation adjustments |