Regulatory Matters - Capital and Risk-Based Capital and Leverage Ratios (Details) $ in Thousands	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Renasant corporation
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital to Average Assets (Leverage) - Amount	$ 1,424,268	$ 1,422,077
Tier 1 Capital to Average Assets (Leverage) - Ratio	0.0900	0.0915
Common Equity Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,316,342	$ 1,314,295
Common Equity Tier 1 Capital to Risk-Weighted Assets - Ratio	10.78%	11.18%
Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,424,268	$ 1,422,077
Tier 1 Capital to Risk-Weighted Assets - Ratio	0.1167	0.1210
Total Capital to Risk-Weighted Assets - Amount	$ 1,892,630	$ 1,897,167
Total Capital to Risk-Weighted Assets - Ratio	0.1550	0.1614
Renasant bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital to Average Assets (Leverage) - Amount	$ 1,581,608	$ 1,580,904
Tier 1 Capital to Average Assets (Leverage) - Ratio	0.1000	0.1018
Common Equity Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,581,608	$ 1,580,904
Common Equity Tier 1 Capital to Risk-Weighted Assets - Ratio	12.95%	13.46%
Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,581,608	$ 1,580,904
Tier 1 Capital to Risk-Weighted Assets - Ratio	0.1295	0.1346
Total Capital to Risk-Weighted Assets - Amount	$ 1,714,725	$ 1,697,163
Total Capital to Risk-Weighted Assets - Ratio	0.1404	0.1444