Regulatory Matters - Capital and Risk-Based Capital and Leverage Ratios (Details) $ in Thousands	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Renasant Corporation
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital to Average Assets (Leverage) - Amount	$ 1,948,348	$ 1,935,522
Tier 1 Capital to Average Assets (Leverage) - Ratio	0.1139	0.1134
Common Equity Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,837,789	$ 1,825,197
Common Equity Tier 1 Capital to Risk-Weighted Assets - Ratio	12.59%	12.73%
Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,948,348	$ 1,935,522
Tier 1 Capital to Risk-Weighted Assets - Ratio	0.1335	0.1350
Total Capital to Risk-Weighted Assets - Amount	$ 2,465,568	$ 2,449,129
Total Capital to Risk-Weighted Assets - Ratio	0.1689	0.1708
Renasant Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital to Average Assets (Leverage) - Amount	$ 1,855,377	$ 1,843,123
Tier 1 Capital to Average Assets (Leverage) - Ratio	0.1085	0.1080
Common Equity Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,855,377	$ 1,843,123
Common Equity Tier 1 Capital to Risk-Weighted Assets - Ratio	12.71%	12.85%
Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,855,377	$ 1,843,123
Tier 1 Capital to Risk-Weighted Assets - Ratio	0.1271	0.1285
Total Capital to Risk-Weighted Assets - Amount	$ 2,038,363	$ 2,022,737
Total Capital to Risk-Weighted Assets - Ratio	0.1396	0.1410