Semi-Annual Consolidated Balance Sheet
| Concept | As at 2024-03-31 | As at 2023-12-31 | 
|---|---|---|
| Semi-annual consolidated balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Current assets | ||
| Cash and deposits | 
                                                190,031,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                147,722,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Securities | 
                                                8,631,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,631,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                15,609,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                16,228,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -12,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -11,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                518,849,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                473,821,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Property, plant and equipment | 
                                                615,489,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                551,994,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Property, plant and equipment | ||
| Buildings and structures | — | — | 
| Buildings and structures, net | 
                                                143,860,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                106,624,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Machinery, equipment and vehicles | — | — | 
| Machinery, equipment and vehicles, net | 
                                                126,009,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                132,950,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Land | 
                                                24,004,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                23,883,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Construction in progress | 
                                                316,648,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                284,061,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | — | — | 
| Other, net | 
                                                4,965,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,474,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | ||
| Other | 
                                                7,605,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,687,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | 
                                                7,605,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,687,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | 
                                                38,526,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                39,583,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | ||
| Investment securities | 
                                                2,131,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,045,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax assets | 
                                                7,195,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,347,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                4,283,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,205,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -292,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -282,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                661,622,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                599,265,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Assets | 
                                                1,180,471,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,073,087,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | ||
| Notes and accounts payable - trade | 
                                                34,439,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                34,213,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Short-term borrowings | 
                                                35,404,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                34,107,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Lease liabilities | 
                                                97,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                92,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Income taxes payable | 
                                                8,613,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,306,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                122,594,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                123,271,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                205,710,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                204,529,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Long-term borrowings | 
                                                293,891,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                190,140,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Lease liabilities | 
                                                146,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                114,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retirement benefit liability | 
                                                23,635,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                24,574,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                16,846,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,034,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | 
                                                334,683,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                233,030,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                540,393,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                437,559,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Provision for bonuses | 
                                                4,560,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,537,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | ||
| Share capital | 
                                                199,034,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                199,034,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | ||
| Capital surplus | 
                                                85,286,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                85,286,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                268,243,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                267,739,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Treasury shares | 
                                                -962,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -964,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | 
                                                551,601,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                551,096,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | ||
| Valuation difference on available-for-sale securities | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred gains or losses on hedges | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                0
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Revaluation reserve for land | 
                                                2,885,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,885,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Foreign currency translation adjustment | 
                                                25,031,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                19,166,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Remeasurements of defined benefit plans | 
                                                -477,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -992,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | 
                                                27,439,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                21,059,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-controlling interests | 
                                                61,036,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                63,371,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                640,078,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                635,527,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                1,180,471,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,073,087,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |