Regulatory Matters - Capital and Risk-based Capital and Leverage Ratios (Details) $ in Thousands	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital to Average Assets (Leverage) - Amount	$ 109,388
Renasant Corporation
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital to Average Assets (Leverage) - Amount	$ 1,578,918	$ 1,481,197
Tier 1 Capital to Average Assets (Leverage) - Ratio	0.0962	0.0936
Common Equity Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,469,531	$ 1,372,747
Common Equity Tier 1 Capital to Risk-Weighted Assets - Ratio	10.52%	10.21%
Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,578,918	$ 1,481,197
Tier 1 Capital to Risk-Weighted Assets - Ratio	0.1130	0.1101
Total Capital to Risk-Weighted Assets - Amount	$ 2,085,531	$ 1,968,001
Total Capital to Risk-Weighted Assets - Ratio	0.1493	0.1463
Renasant Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital to Average Assets (Leverage) - Amount	$ 1,714,965	$ 1,630,389
Tier 1 Capital to Average Assets (Leverage) - Ratio	0.1045	0.1030
Common Equity Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,714,965	$ 1,630,389
Common Equity Tier 1 Capital to Risk-Weighted Assets - Ratio	12.25%	12.10%
Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,714,965	$ 1,630,389
Tier 1 Capital to Risk-Weighted Assets - Ratio	0.1225	0.1210
Total Capital to Risk-Weighted Assets - Amount	$ 1,888,104	$ 1,781,312
Total Capital to Risk-Weighted Assets - Ratio	0.1349	0.1322

Common Equity Tier One Risk Based Capital

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Common Equity Tier One Risk Based Capital to Risk Weighted Assets

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Amount of total capital as defined by regulatory framework.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480696/942-505-50-1

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Ratio of total risk-based capital to risk-weighted assets as defined by regulatory framework.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480696/942-505-50-1B

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 942
-SubTopic 505
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480696/942-505-50-1

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Amount of Tier 1 leverage capital as defined by regulatory framework.

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Ratio of Tier 1 capital to average assets as defined by regulatory framework.

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