Quarterly Consolidated Balance Sheet
| Concept | As at 2024-03-31 | As at 2023-12-31 | 
|---|---|---|
| Quarterly consolidated balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Current assets | ||
| Cash and deposits | 
                                                4,042,882,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,846,196,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Merchandise and finished goods | 
                                                85,443,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                92,451,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Work in process | 
                                                146,517,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                231,955,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Raw materials and supplies | 
                                                19,109,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,393,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                392,559,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                343,993,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -4,609,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -4,545,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                7,912,193,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,643,737,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Property, plant and equipment | 
                                                2,502,481,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,525,372,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Property, plant and equipment | ||
| Buildings and structures | — | — | 
| Buildings and structures, net | 
                                                1,438,866,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,457,392,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Land | 
                                                945,794,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                945,794,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | — | — | 
| Other, net | 
                                                117,821,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                122,185,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | ||
| Goodwill | 
                                                37,998,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                42,220,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                77,392,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                80,854,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | 
                                                115,391,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                123,075,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | 
                                                591,050,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                475,328,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | ||
| Other | 
                                                593,900,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                478,178,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -2,850,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -2,850,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                3,208,923,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,123,775,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Assets | 
                                                11,121,116,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,767,513,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | ||
| Notes and accounts payable - trade | 
                                                436,258,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                547,213,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Short-term borrowings | 
                                                670,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                700,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Income taxes payable | 
                                                267,156,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                202,856,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                359,253,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                315,639,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                2,714,879,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,461,503,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Retirement benefit liability | 
                                                10,173,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,545,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                4,443,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,443,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                76,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                114,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | 
                                                14,693,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                14,103,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                2,729,573,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,475,607,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | ||
| Shareholders' equity | ||
| Share capital | 
                                                940,327,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                940,327,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | 
                                                1,171,768,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,171,768,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                6,245,078,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,162,775,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Treasury shares | 
                                                -26,362,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -26,107,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | 
                                                8,330,811,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,248,764,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | ||
| Valuation difference on available-for-sale securities | 
                                                51,676,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                35,426,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Foreign currency translation adjustment | 
                                                9,055,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,714,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | 
                                                60,731,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                43,141,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                8,391,543,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,291,905,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                11,121,116,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,767,513,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |