Consolidated Balance Sheet
| Concept | As at 2024-03-31 | As at 2023-12-31 | 
|---|---|---|
| Consolidated balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Non-current assets | 
                                                2,686,800,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,709,108,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | 
                                                2,169,141,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,167,006,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investment securities | 
                                                296,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                296,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax assets | 
                                                369,199,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                419,285,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                87,842,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                87,842,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Property, plant and equipment | ||
| Buildings, net | 
                                                240,584,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                252,933,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Property, plant and equipment | 
                                                267,914,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                282,287,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | ||
| Goodwill | 
                                                228,306,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                235,671,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                1,384,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,420,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other intangible assets | ||
| Intangible assets | 
                                                249,744,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                259,814,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Software | 
                                                9,115,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,222,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | ||
| Current assets | ||
| Cash and deposits | 
                                                3,928,533,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,838,745,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                301,880,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                325,208,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -13,168,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -15,247,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                7,284,707,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,159,931,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Operational investment securities | 
                                                2,049,615,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                516,904,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred assets | 
                                                5,208,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,642,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Organization expenses | 
                                                5,208,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,642,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred assets | ||
| Assets | 
                                                9,976,717,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,874,682,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Non-current liabilities | ||
| Long-term borrowings | 
                                                1,293,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,352,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | 
                                                1,424,324,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,483,303,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Asset retirement obligations | 
                                                131,324,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                131,303,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | ||
| Short-term borrowings | 
                                                600,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Accounts payable - other | 
                                                208,447,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                183,039,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current portion of long-term borrowings | 
                                                236,956,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                237,313,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Income taxes payable | 
                                                22,268,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                421,277,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Provisions | ||
| Provision for bonuses | 
                                                91,642,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                994,085,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                871,502,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                552,345,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                2,147,109,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,569,015,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Provision for bonuses for directors (and other officers) | 
                                                1,533,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                43,555,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                3,571,433,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,052,318,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | ||
| Shareholders' equity | 
                                                3,255,077,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,699,747,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share capital | 
                                                384,245,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                374,743,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | 
                                                747,083,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                734,019,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                2,132,111,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,599,348,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Treasury shares | 
                                                -8,363,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -8,363,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | 
                                                49,347,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,198,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Foreign currency translation adjustment | 
                                                49,347,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,198,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share award rights | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                19,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Share acquisition rights | 
                                                39,821,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                37,130,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-controlling interests | 
                                                3,061,037,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,065,287,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                6,405,283,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                6,822,364,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                9,976,717,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,874,682,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | ||
| Shareholders' equity | ||
| Valuation and translation adjustments |