Quarterly Consolidated Balance Sheet
| Concept | As at 2023-09-30 | As at 2023-06-30 | 
|---|---|---|
| Quarterly consolidated balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Current assets | ||
| Cash and deposits | 
                                                2,263,108,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,320,739,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Securities | 
                                                400,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                500,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                184,087,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                176,557,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -96,804,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -96,745,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                3,466,248,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,571,502,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Property, plant and equipment | 
                                                25,965,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                27,524,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Property, plant and equipment | ||
| Intangible assets | ||
| Intangible assets | 
                                                5,354,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,751,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | 
                                                414,540,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                427,014,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | ||
| Other | 
                                                415,222,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                427,696,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -682,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -682,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                445,861,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                460,290,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred assets | 
                                                761,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,015,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred assets | ||
| Assets | 
                                                3,912,871,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,032,808,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | ||
| Short-term borrowings | 
                                                600,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                600,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Income taxes payable | 
                                                22,092,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                26,221,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                311,898,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                285,120,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                1,743,481,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,835,654,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Long-term borrowings | 
                                                1,908,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,265,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                20,010,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                19,973,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                8,185,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,636,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | 
                                                30,103,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                30,875,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                1,773,584,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,866,529,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | ||
| Shareholders' equity | ||
| Share capital | 
                                                1,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | 
                                                1,495,568,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,494,271,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                66,802,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                88,175,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Treasury shares | 
                                                -434,362,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -434,362,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | 
                                                2,128,008,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,148,083,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | ||
| Valuation difference on available-for-sale securities | 
                                                12,923,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,399,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Foreign currency translation adjustment | 
                                                -1,646,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -203,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | 
                                                11,277,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,195,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                2,139,286,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,166,279,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                3,912,871,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,032,808,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |