Employee Benefit and Deferred Compensation Plans - Additional Information (Details)	12 Months Ended
	Dec. 31, 2021 USD ($) plan point shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2007 officer
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accumulated benefit obligation	$ 27,567,000	$ 28,226,000
Retiring age limit, minimum	55 years
Retiring age limit, maximum	65 years
Eligible employee from service (in years)	15 years
Number of points for eligibility (points) | point	70
Minimum eligible age for Medicare coverage	65 years
Health care cost trend rate (percent)	5.00%
Redemption notice	60 days
Employee deferrals (percent)	4.00%
Percentage of plan compensation as nondiscretionary contribution	5.00%
Percentage of plan compensation in excess of social security wage base	5.00%
Hours of service credited to the employees during the year	1000 hours
Employee deferrals amounts	$ 11,919,000	17,888,000	$ 16,009,000
Number of conventional deferred compensation plans | plan	2
Company's deferred compensation plan expense	$ 3,274,000	3,965,000	3,610,000
Number of officers provided for | officer				4
Expiration period subsequent to retirement				15 years
Supplemental executive retirement liabilities totaled	3,679,000	3,816,000
Incentive compensation plan expense	$ 8,609,000	$ 6,425,000	$ 4,200,000
Option expiration period	10 years
Granted (shares) | shares	0	0	0
Intrinsic value of options exercised	$ 262,000	$ 279,000	$ 290,000
Common shares reserved for issuance under employee benefit plans (shares) | shares	2,828,818
401(k) Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Common shares reserved for issuance under employee benefit plans (shares) | shares	977,956
Deferred Stock Unit Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Common shares reserved for issuance under employee benefit plans (shares) | shares	159,111
2011 Long-Term Incentive Compensation Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Common shares reserved for issuance under employee benefit plans (shares) | shares	1,447,883
Stock compensation plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Compensation expense	$ 0	0	0
Performance- Based Restricted Stock
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Compensation expense	9,882,000	10,419,000	10,046,000
Time- Based Restricted Stock
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Unrecognized stock-based compensation expense	$ 10,584,000
Weighted average period over which unrecognized expense is expected to be recognized (in years)	1 year 9 months 7 days
Growth Investment
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Equity income strategy (percent)	77.00%
Real Estate | Growth Investment
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Equity income strategy (percent)	6.00%
Interest rate contracts | Growth Investment
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Equity income strategy (percent)	23.00%
Pension Benefits Renasant
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Company contribution to pension benefit plan	$ 0	0
Accumulated benefit obligation	27,567,000	28,226,000	$ 28,020,000
Other Postretirement Benefits Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Company contribution to pension benefit plan	231,000	$ 214,000
Expected company contributions	$ 176,000