Regulatory Matters - Summary of Capital Requirements (Details) $ in Thousands |
Mar. 31, 2026
USD ($)
|
Dec. 31, 2025
USD ($)
|
|---|---|---|
| BancPlus Corporation | ||
| Actual | ||
| Tier 1 Capital to Average Assets | $ 859,629 | $ 862,204 |
| Tier 1 Capital to Average Assets, ratio (as a percentage) | 0.1059 | 0.1091 |
| Minimum Required to be Well Capitalized | ||
| Tier 1 Capital to Average Assets | $ 730,693 | $ 711,404 |
| Tier 1 Capital to Average Assets, ratio (as a percentage) | 0.09 | 0.09 |
| Subsidiaries | ||
| Actual | ||
| Tier 1 Capital to Average Assets | $ 873,989 | $ 844,129 |
| Tier 1 Capital to Average Assets, ratio (as a percentage) | 0.1077 | 0.1067 |
| Minimum Required to be Well Capitalized | ||
| Tier 1 Capital to Average Assets | $ 730,378 | $ 711,795 |
| Tier 1 Capital to Average Assets, ratio (as a percentage) | 0.09 | 0.09 |