Regulatory Matters - Capital and Risk-Based Capital and Leverage Ratios (Details) $ in Thousands	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Renasant Corporation
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital to Average Assets (Leverage) - Amount	$ 1,503,086	$ 1,481,197
Tier 1 Capital to Average Assets (Leverage) - Ratio	0.0918	0.0936
Common Equity Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,394,401	$ 1,372,747
Common Equity Tier 1 Capital to Risk-Weighted Assets - Ratio	10.19%	10.21%
Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,503,086	$ 1,481,197
Tier 1 Capital to Risk-Weighted Assets - Ratio	0.1098	0.1101
Total Capital to Risk-Weighted Assets - Amount	$ 2,009,552	$ 1,968,001
Total Capital to Risk-Weighted Assets - Ratio	0.1468	0.1463
Renasant Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital to Average Assets (Leverage) - Amount	$ 1,651,005	$ 1,630,389
Tier 1 Capital to Average Assets (Leverage) - Ratio	0.1008	0.1030
Common Equity Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,651,005	$ 1,630,389
Common Equity Tier 1 Capital to Risk-Weighted Assets - Ratio	12.03%	12.10%
Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,651,005	$ 1,630,389
Tier 1 Capital to Risk-Weighted Assets - Ratio	0.1203	0.1210
Total Capital to Risk-Weighted Assets - Amount	$ 1,821,367	$ 1,781,312
Total Capital to Risk-Weighted Assets - Ratio	0.1328	0.1322