Semi-Annual Consolidated Balance Sheet
| Concept | As at 2023-12-31 | As at 2023-03-31 | 
|---|---|---|
| Semi-annual consolidated balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Current assets | ||
| Cash and deposits | 
                                                6,552,026,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,584,111,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Inventories | 
                                                122,203,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                99,140,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                50,779,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                50,927,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -6,463,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -9,069,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                8,073,855,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,217,721,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Property, plant and equipment | 
                                                4,235,708,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,273,780,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Property, plant and equipment | ||
| Land | 
                                                1,710,972,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,710,972,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Leased assets | — | — | 
| Leased assets, net | 
                                                8,931,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,967,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Construction in progress | 
                                                43,780,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                31,102,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | ||
| Other | 
                                                10,716,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,716,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | 
                                                240,466,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                267,176,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | 
                                                972,662,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,003,565,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | ||
| Investment securities | 
                                                76,319,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                67,997,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Long-term loans receivable | 
                                                1,078,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                290,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax assets | 
                                                301,915,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                304,306,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                152,383,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                193,399,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -83,870,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -83,554,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                5,448,837,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,544,522,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Assets | 
                                                13,522,693,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                13,762,244,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | ||
| Lease liabilities | 
                                                4,006,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,006,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Income taxes payable | 
                                                73,802,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                121,716,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                1,111,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,111,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                278,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                5,990,629,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,261,203,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Lease liabilities | 
                                                6,837,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,077,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                14,670,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                14,670,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                18,469,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,469,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | 
                                                230,922,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                208,842,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                6,221,551,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,470,046,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Provision for retirement benefits for directors (and other officers) | 
                                                78,910,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                74,860,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Provision for bonuses | 
                                                86,843,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                165,005,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | ||
| Shareholders' equity | ||
| Share capital | 
                                                923,761,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                923,761,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | 
                                                770,533,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                770,533,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                5,573,366,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,570,048,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Treasury shares | 
                                                -135,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -85,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | 
                                                7,267,524,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,264,257,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | ||
| Valuation difference on available-for-sale securities | 
                                                33,616,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                27,940,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | 
                                                33,616,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                27,940,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                7,301,141,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,292,198,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                13,522,693,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                13,762,244,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |