Balance Sheet
| Concept | As at 2023-12-31 | As at 2023-03-31 | 
|---|---|---|
| Balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Current assets | 
                                                2,027,866,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,623,185,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Cash and deposits | 
                                                1,511,812,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,183,763,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accounts receivable - trade | 
                                                317,423,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                260,614,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                198,875,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                178,951,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -245,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -144,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Property, plant and equipment | ||
| Property, plant and equipment | 
                                                1,898,878,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,672,299,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other, net | 
                                                281,582,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                230,730,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                874,784,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                890,570,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accumulated depreciation | 
                                                -593,202,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -659,839,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Own-used assets | ||
| Intangible assets | ||
| Goodwill | 
                                                4,553,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,604,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | 
                                                7,187,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,116,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                2,634,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,512,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other intangible assets | ||
| Investments and other assets | ||
| Investments and other assets | 
                                                1,423,938,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,463,521,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax assets | 
                                                299,272,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                374,198,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                333,573,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                274,253,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                3,330,005,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,143,937,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other assets | — | — | 
| Current assets | ||
| Other assets | ||
| Assets | 
                                                5,357,872,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,767,123,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | 
                                                1,901,767,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,670,563,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accounts payable - trade | 
                                                302,857,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                237,344,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accounts payable - other | 
                                                404,471,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                367,453,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Income taxes payable | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                19,916,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                270,858,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                239,533,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                2,191,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,908,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Non-current liabilities | 
                                                2,341,052,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,158,913,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Long-term borrowings | 
                                                1,887,781,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,815,860,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                155,382,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                60,182,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                297,889,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                282,871,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | ||
| Current portion of long-term borrowings | 
                                                921,388,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                801,408,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                4,242,820,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,829,477,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other liabilities | — | — | 
| Other liabilities | — | — | 
| Liabilities and net assets | ||
| Shareholders' equity | 
                                                1,063,095,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                909,685,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share capital | 
                                                35,838,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                172,149,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | 
                                                1,203,011,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,055,024,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                -175,754,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -317,487,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | 
                                                21,922,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,372,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation difference on available-for-sale securities | 
                                                21,922,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,372,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share acquisition rights | 
                                                22,555,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                16,916,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                1,115,051,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                937,645,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                5,357,872,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,767,123,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | ||
| Valuation and translation adjustments | ||
| Shareholders' equity | ||
| Capital surplus | ||
| Retained earnings |