Shareholders' Equity - Changes in Number of Issued Shares of Common Stock and Common Stock Held by SMFG or its Subsidiaries (Detail) - shares |
12 Months Ended | ||
|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2024 |
|
| Common stock [member] | |||
| Disclosure of classes of share capital [line items] | |||
| At beginning of period | 3,884,445,458 | 4,012,587,252 | 4,124,073,582 |
| Net change | (56,947,318) | (128,141,794) | (111,486,330) |
| At end of period | 3,827,498,140 | 3,884,445,458 | 4,012,587,252 |
| Treasury stock [member] | |||
| Disclosure of classes of share capital [line items] | |||
| At beginning of period | 10,651,848 | 70,763,598 | 90,211,950 |
| Net change | (19,729) | (60,111,750) | (19,448,352) |
| At end of period | 10,632,119 | 10,651,848 | 70,763,598 |