Semi-Annual Balance Sheet
| Concept | As at 2024-03-31 | As at 2023-12-31 | 
|---|---|---|
| Semi-annual balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Current assets | ||
| Cash and deposits | 
                                                47,501,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                65,240,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                6,848,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,429,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -6,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -6,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                86,240,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                106,913,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Property, plant and equipment | 
                                                130,679,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                130,108,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Property, plant and equipment | ||
| Machinery and equipment | — | — | 
| Machinery and equipment, net | 
                                                15,535,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                15,938,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Tools, furniture and fixtures | — | — | 
| Tools, furniture and fixtures, net | 
                                                8,028,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,176,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Land | 
                                                25,293,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                23,909,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Leased assets | — | — | 
| Leased assets, net | 
                                                262,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                304,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Construction in progress | 
                                                961,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                838,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | ||
| Intangible assets | 
                                                10,947,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                11,175,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Goodwill | 
                                                346,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                435,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Software | 
                                                9,907,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,045,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                694,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                694,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | ||
| Investment securities | 
                                                8,056,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,056,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | 
                                                61,531,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                63,196,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Long-term loans receivable | 
                                                9,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax assets | 
                                                7,429,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,762,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                3,556,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,456,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -1,214,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,216,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                203,159,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                204,480,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Assets | 
                                                289,399,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                311,393,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | ||
| Accounts payable - trade | 
                                                1,232,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,694,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Lease liabilities | 
                                                202,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                224,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Income taxes payable | 
                                                4,076,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,630,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                246,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                252,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                1,797,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,838,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                53,803,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                77,024,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accounts payable - other | 
                                                26,979,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                34,570,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Non-current liabilities | 
                                                7,781,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,695,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Lease liabilities | 
                                                131,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                168,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                4,973,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,987,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                204,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                204,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                61,585,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                84,720,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other liabilities | — | — | 
| Provision for retirement benefits for directors (and other officers) | 
                                                359,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                262,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Provision for bonuses | 
                                                821,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,796,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax liabilities | 
                                                30,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                33,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax liabilities for land revaluation | 
                                                289,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                289,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other liabilities | — | — | 
| Net assets | ||
| Shareholders' equity | ||
| Share capital | 
                                                24,113,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                24,113,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | ||
| Capital surplus | 
                                                42,124,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                42,124,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | ||
| Retained earnings | 
                                                165,706,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                164,558,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Treasury shares | 
                                                -3,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | 
                                                231,941,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                230,794,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | ||
| Valuation and translation adjustments | 
                                                -4,126,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -4,120,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Revaluation reserve for land | 
                                                -4,202,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -4,202,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                227,814,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                226,673,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                289,399,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                311,393,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |