Defined Benefit and Other Postretirement Benefits - Additional Information (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($)
The Continuing Plan [Member] \| Scenario Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Trustmark's minimum required contribution to the Trustmark Corporation Pension Plan for Certain Employees of Acquired Financial Institutions	$ 160

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.

No definition available.

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