Goodwill - Schedule of Reconciliation of Changes in Goodwill (Details) - Goodwill - JPY (¥) ¥ in Millions |
12 Months Ended | |
|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Reconciliation of changes in intangible assets and goodwill [abstract] | ||
| As of beginning of the year | ¥ 5,324,430 | ¥ 5,410,067 |
| Reclassification to assets held for sale (Note 18) | (11,714) | (6,999) |
| Foreign currency translation differences and others | 496,293 | (78,637) |
| As of end of the year | ¥ 5,809,010 | ¥ 5,324,430 |