Quarterly Consolidated Balance Sheet
| Concept | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-09-30 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2024-03-31 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-09-30 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | As at 2023-03-31 | 
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Quarterly consolidated balance sheet | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Balance sheet | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Assets | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Current assets | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Cash and deposits | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                1,032,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                1,221,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Other | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                3,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Current assets | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                1,032,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                1,731,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Non-current assets | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Property, plant and equipment | — | — | — | — | — | — | — | 
                                                78,675,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                74,832,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Property, plant and equipment | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Accumulated depreciation | — | — | — | — | — | — | — | 
                                                -53,580,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                -54,663,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Intangible assets | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Other | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                1,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Intangible assets | — | — | — | — | — | — | — | 
                                                12,568,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                16,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                14,835,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                18,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Investments and other assets | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                501,112,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                501,111,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Investments and other assets | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Deferred tax assets | — | — | — | — | — | — | — | 
                                                273,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                51,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                279,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                50,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Non-current assets | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                501,128,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                501,130,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Assets | — | — | — | — | — | 
                                                511,423,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,616,033,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,073,993,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                502,160,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                9,104,609,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                68,315,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,036,293,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -542,040,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                9,258,385,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                502,861,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                512,671,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,788,767,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                9,319,771,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                8,752,378,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                54,722,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -531,004,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,807,100,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Liabilities | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Current liabilities | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Income taxes payable | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                36,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                15,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Other | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                46,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                21,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Current liabilities | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                169,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                119,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Non-current liabilities | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Retirement benefit liability | — | — | — | — | — | — | — | 
                                                8,747,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                8,761,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Non-current liabilities | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                70,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                61,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Reserves under special laws | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Reserves under special laws | — | — | — | — | — | — | — | 
                                                7,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                6,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Liabilities | — | — | — | — | — | 
                                                8,085,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,252,914,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,207,459,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                239,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                8,244,829,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                46,111,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,198,717,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -45,455,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                8,415,357,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                180,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                8,032,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,004,322,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                8,038,708,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                7,998,438,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                32,237,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -34,386,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,030,676,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Net assets | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Shareholders' equity | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Share capital | — | — | — | — | — | — | — | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Capital surplus | — | — | — | — | — | — | — | 
                                                27,724,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                479,182,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                27,700,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                479,158,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Retained earnings | — | — | — | — | — | — | — | 
                                                540,885,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                16,365,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                516,974,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                12,304,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Treasury shares | — | — | — | — | — | — | — | 
                                                -13,741,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                -13,741,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                -8,900,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                -8,900,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Shareholders' equity | — | — | — | — | — | — | — | 
                                                574,868,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                501,806,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                555,773,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                502,562,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Valuation and translation adjustments | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Valuation difference on available-for-sale securities | — | — | — | — | — | — | — | 
                                                253,788,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                250,412,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Deferred gains or losses on hedges | — | — | — | — | — | — | — | 
                                                4,618,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                2,664,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Revaluation reserve for land | — | — | — | — | — | — | — | 
                                                18,733,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                18,765,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Remeasurements of defined benefit plans | — | — | — | — | — | — | — | 
                                                14,120,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                15,002,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Valuation and translation adjustments | — | — | — | — | — | — | — | 
                                                291,259,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                286,845,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Share acquisition rights | — | — | — | — | — | — | — | 
                                                115,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                115,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                119,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                119,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Non-controlling interests | — | — | — | — | — | — | — | 
                                                291,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                289,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
| Net assets | 
                                                4,618,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -13,741,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                16,365,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,733,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                14,120,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | 
                                                866,534,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                115,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                291,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                16,365,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                501,806,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                501,921,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                479,182,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                540,885,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                115,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -13,741,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                474,182,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                253,788,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                574,868,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                291,259,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                27,724,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                2,664,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                119,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                289,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                15,002,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                502,562,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -8,900,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                12,304,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                250,412,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                27,700,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                516,974,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                12,304,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                479,158,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -8,900,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                474,158,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                843,027,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                555,773,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                119,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                286,845,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                502,681,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,765,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,810,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                4,581,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,683,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                311,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                784,444,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -4,577,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,683,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -4,577,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                235,609,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,730,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                119,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | 
                                                503,383,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                479,158,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                503,264,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                474,158,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                548,404,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                203,487,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                27,700,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                505,281,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                119,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                149,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                232,307,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,811,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                20,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                8,811,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                474,156,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                527,072,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                504,325,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                202,105,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                27,698,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                479,156,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,792,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                -3,792,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                9,612,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                309,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                759,838,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                5,000,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                504,176,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                483,166,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                149,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                18,977,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
                                                1,611,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | 
| Liabilities and net assets | — | — | — | — | — | — | — | 
                                                9,073,993,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | 
                                                502,160,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 
                                                9,258,385,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | 
                                                502,861,000,000
                                                
                                                    
                                                        JPY
                                                    
                                                
                                             | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — |