Quarterly Consolidated Balance Sheet
| Concept | As at 2024-06-30 | As at 2023-12-31 | 
|---|---|---|
| Quarterly consolidated balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Current assets | ||
| Cash and deposits | 
                                                56,788,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                65,240,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Raw materials and supplies | 
                                                1,239,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,581,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                5,849,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,429,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -6,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -6,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                91,758,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                106,913,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Property, plant and equipment | 
                                                135,218,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                130,108,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Property, plant and equipment | ||
| Buildings and structures | — | — | 
| Buildings and structures, net | 
                                                82,381,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                80,940,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Land | 
                                                26,976,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                23,909,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Leased assets | — | — | 
| Leased assets, net | 
                                                268,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                304,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Construction in progress | 
                                                1,212,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                838,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | ||
| Goodwill | 
                                                409,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                435,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                694,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                694,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | 
                                                10,888,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                11,175,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | 
                                                65,604,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                63,196,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | ||
| Investment securities | 
                                                13,056,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,056,000,000
                                                
                                                    
                                                        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 | 
                                                3,568,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,456,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -1,215,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,216,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                211,711,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                204,480,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Assets | 
                                                303,470,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                311,393,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | ||
| Income taxes payable | 
                                                8,341,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,630,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                205,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                252,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                4,176,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,838,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                60,414,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                77,024,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Retirement benefit liability | 
                                                1,282,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,300,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                4,790,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,987,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                203,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                204,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | 
                                                7,085,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,695,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                67,500,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                84,720,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | ||
| Shareholders' equity | ||
| Share capital | 
                                                24,113,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                24,113,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | 
                                                42,124,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                42,124,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                173,868,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                164,558,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Treasury shares | 
                                                -3,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | 
                                                240,103,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                230,794,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | ||
| Revaluation reserve for land | 
                                                -4,202,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -4,202,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Remeasurements of defined benefit plans | 
                                                68,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                81,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | 
                                                -4,133,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -4,120,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                235,969,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                226,673,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                303,470,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                311,393,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |