Regulatory Matters - Capital and Risk-Based Capital and Leverage Ratios (Details) $ in Thousands	Sep. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)
Renasant Corporation
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital to Average Assets (Leverage) - Amount	$ 1,904,006	$ 1,578,918
Tier 1 Capital to Average Assets (Leverage) - Ratio	0.1132	0.0962
Common Equity Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,793,916	$ 1,469,531
Common Equity Tier 1 Capital to Risk-Weighted Assets - Ratio	12.88%	10.52%
Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,904,006	$ 1,578,918
Tier 1 Capital to Risk-Weighted Assets - Ratio	0.1367	0.1130
Total Capital to Risk-Weighted Assets - Amount	$ 2,412,254	$ 2,085,531
Total Capital to Risk-Weighted Assets - Ratio	0.1732	0.1493
Renasant Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital to Average Assets (Leverage) - Amount	$ 1,814,955	$ 1,714,965
Tier 1 Capital to Average Assets (Leverage) - Ratio	0.1080	0.1045
Common Equity Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,814,955	$ 1,714,965
Common Equity Tier 1 Capital to Risk-Weighted Assets - Ratio	13.03%	12.25%
Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,814,955	$ 1,714,965
Tier 1 Capital to Risk-Weighted Assets - Ratio	0.1303	0.1225
Total Capital to Risk-Weighted Assets - Amount	$ 1,989,433	$ 1,888,104
Total Capital to Risk-Weighted Assets - Ratio	0.1428	0.1349