Quarterly Consolidated Balance Sheet
| Concept | As at 2024-09-30 | As at 2024-03-31 | 
|---|---|---|
| Quarterly consolidated balance sheet | ||
| Balance sheet | ||
| Assets | ||
| Current assets | ||
| Cash and deposits | 
                                                12,497,326,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                12,455,846,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Securities | 
                                                404,376,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                202,306,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Work in process | 
                                                1,422,605,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,308,033,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Raw materials and supplies | 
                                                3,353,360,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,093,096,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                284,973,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                266,518,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -5,429,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -5,609,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current assets | 
                                                36,808,976,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                36,294,939,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | ||
| Property, plant and equipment | 
                                                16,387,080,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                16,240,355,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Property, plant and equipment | ||
| Buildings and structures | — | — | 
| Buildings and structures, net | 
                                                3,485,034,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,471,206,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Machinery, equipment and vehicles | — | — | 
| Machinery, equipment and vehicles, net | 
                                                3,263,764,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,035,654,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Land | 
                                                9,003,482,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,003,482,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Construction in progress | 
                                                421,465,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                525,498,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | — | — | 
| Other, net | 
                                                213,334,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                204,513,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | ||
| Other | 
                                                2,954,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,971,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Intangible assets | 
                                                237,860,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                88,190,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | 
                                                19,824,800,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                20,981,715,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Investments and other assets | ||
| Investment securities | 
                                                17,973,948,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                19,159,944,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Long-term loans receivable | 
                                                8,845,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,989,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Deferred tax assets | 
                                                1,036,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,036,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                1,436,530,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,417,988,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Allowance for doubtful accounts | 
                                                -28,830,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -28,830,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current assets | 
                                                36,449,742,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                37,310,261,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Assets | 
                                                73,258,718,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                73,605,200,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | ||
| Current liabilities | ||
| Notes and accounts payable - trade | 
                                                2,715,241,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,151,396,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Short-term borrowings | 
                                                750,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                750,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Income taxes payable | 
                                                342,250,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                422,669,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                451,616,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                749,784,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Current liabilities | 
                                                12,053,146,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                11,263,148,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | ||
| Long-term borrowings | 
                                                1,630,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,110,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retirement benefit liability | 
                                                2,209,553,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,129,495,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Other | 
                                                62,169,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                62,545,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-current liabilities | 
                                                6,329,797,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                7,004,223,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities | 
                                                18,382,944,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,267,372,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | ||
| Shareholders' equity | ||
| Share capital | 
                                                10,720,068,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,720,068,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Capital surplus | 
                                                10,888,051,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                10,888,051,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Retained earnings | 
                                                25,705,408,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                25,523,331,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Treasury shares | 
                                                -1,342,155,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -1,232,269,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Shareholders' equity | 
                                                45,971,372,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                45,899,181,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | ||
| Valuation difference on available-for-sale securities | 
                                                4,869,770,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,492,889,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Foreign currency translation adjustment | 
                                                315,068,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                259,099,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Remeasurements of defined benefit plans | 
                                                128,734,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                140,205,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Valuation and translation adjustments | 
                                                5,313,573,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,892,194,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Non-controlling interests | 
                                                3,590,828,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                3,546,452,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Net assets | 
                                                54,875,774,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                55,337,828,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | 
                                                73,258,718,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                73,605,200,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             |