Regulatory Matters - Capital and Risk-Based Capital and Leverage Ratios (Details) $ in Thousands	Mar. 31, 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	$ 1,594,020	$ 1,578,918
Tier 1 Capital to Average Assets (Leverage) - Ratio	0.0975	0.0962
Common Equity Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,484,398	$ 1,469,531
Common Equity Tier 1 Capital to Risk-Weighted Assets - Ratio	10.59%	10.52%
Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,594,020	$ 1,578,918
Tier 1 Capital to Risk-Weighted Assets - Ratio	0.1137	0.1130
Total Capital to Risk-Weighted Assets - Amount	$ 2,102,933	$ 2,085,531
Total Capital to Risk-Weighted Assets - Ratio	0.1500	0.1493
Renasant Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Capital to Average Assets (Leverage) - Amount	$ 1,728,934	$ 1,714,965
Tier 1 Capital to Average Assets (Leverage) - Ratio	0.1057	0.1045
Common Equity Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,728,934	$ 1,714,965
Common Equity Tier 1 Capital to Risk-Weighted Assets - Ratio	12.31%	12.25%
Tier 1 Capital to Risk-Weighted Assets - Amount	$ 1,728,934	$ 1,714,965
Tier 1 Capital to Risk-Weighted Assets - Ratio	0.1231	0.1225
Total Capital to Risk-Weighted Assets - Amount	$ 1,904,816	$ 1,888,104
Total Capital to Risk-Weighted Assets - Ratio	0.1356	0.1349

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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- Definition

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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Amount of Tier 1 risk-based capital as defined by regulatory framework.

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