Regulatory Matters - Capital and Risk-based Capital and Leverage Ratios (Details) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Renasant Corporation
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Amount Included in Tier 1 Capital	$ 1,422,077	$ 1,306,597
Tier 1 Capital to Average Assets (Leverage) (percent)	0.0915	0.0937
Common Equity Tier One Capital to Risk - Weighted Assets, amount	$ 1,314,295	$ 1,199,394
Common Equity Tier One Capital to Risk - Weighted Assets (percent)	11.18%	10.93%
Tier 1 Capital to Risk -Weighted Assets, amount	$ 1,422,077	$ 1,306,597
Tier 1 Capital to Risk - Weighted Assets (percent)	0.1210	0.1191
Total Capital to Risk - Weighted Assets, amount	$ 1,897,167	$ 1,653,694
Total Capital to Risk - Weighted Assets (percent)	0.1614	0.1507
Renasant Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Amount Included in Tier 1 Capital	$ 1,580,904	$ 1,369,994
Tier 1 Capital to Average Assets (Leverage) (percent)	0.1018	0.0983
Common Equity Tier One Capital to Risk - Weighted Assets, amount	$ 1,580,904	$ 1,369,994
Common Equity Tier One Capital to Risk - Weighted Assets (percent)	13.46%	12.49%
Tier 1 Capital to Risk -Weighted Assets, amount	$ 1,580,904	$ 1,369,994
Tier 1 Capital to Risk - Weighted Assets (percent)	0.1346	0.1249
Total Capital to Risk - Weighted Assets, amount	$ 1,697,163	$ 1,504,985
Total Capital to Risk - Weighted Assets (percent)	0.1444	0.1373