Business, Basis of Financial Statement Presentation and Principles of Consolidation	9 Months Ended
Sep. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Business, Basis of Financial Statement Presentation and Principles of Consolidation	Note 1 – Business, Basis of Financial Statement Presentation and Principles of Consolidation Trustmark Corporation (Trustmark) is a bank holding company headquartered in Jackson, Mississippi. Through its subsidiaries, Trustmark operates as a financial services organization providing banking and financial solutions to corporate institutions and individual customers through 187 offices at September 30, 2020 in Alabama, Florida, Mississippi, Tennessee and Texas. The consolidated financial statements include the accounts of Trustmark and all other entities in which Trustmark has a controlling financial interest. All significant intercompany accounts and transactions have been eliminated in consolidation. Certain reclassifications have been made to prior period amounts to conform to the current period presentation. The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the consolidated financial statements, and notes thereto, included in Trustmark’s Annual Report on Form 10-K for its fiscal year ended December 31, 2019 (2019 Annual Report). Operating results for the interim periods disclosed herein are not necessarily indicative of the results that may be expected for a full year or any future period. In the opinion of Management, all adjustments (consisting of normal recurring accruals) considered necessary for the fair presentation of these consolidated financial statements have been included. The preparation of financial statements in conformity with these accounting principles requires Management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and income and expense during the reporting periods and the related disclosures. Although Management’s estimates contemplate current conditions and how they are expected to change in the future, it is reasonably possible that in 2020 actual conditions could vary from those anticipated, which could affect Trustmark’s financial condition and results of operations. Actual results could differ from those estimates. Coronavirus 2019 (COVID-19) Pandemic On March 11, 2020, the World Health Organization declared COVID-19, the disease caused by the novel coronavirus, a pandemic as a result of the global spread of the coronavirus illness. The COVID-19 pandemic has adversely affected, and may continue to adversely affect economic activity globally, nationally and locally. In response to the outbreak, federal and state authorities in the United States introduced various measures to try to limit or slow the spread of the virus, including travel restrictions, nonessential business closures, stay-at-home orders, and strict social distancing. The full impact of the COVID-19 pandemic is unknown and rapidly evolving. It has caused substantial disruption in international and U.S. economies, markets, and employment. The COVID-19 pandemic may continue to have a significant adverse impact on certain industries Trustmark serves, including restaurants and food services, hotels, retail and energy. Because of the significant uncertainties related to the ultimate duration of the COVID-19 pandemic and its potential effects on customers and prospects, and on the national and local economy as a whole, there can be no assurances as to how the crisis may ultimately affect Trustmark’s loan portfolio. It is unknown how long the adverse conditions associated with the COVID-19 pandemic will last and what the complete financial effect will be to Trustmark. It is reasonably possible that estimates made in the financial statements could be materially and adversely impacted in the near term as a result of these conditions, including expected credit losses on loans and off-balance sheet credit exposures. See Note 3 – LHFI and Allowance for Credit Losses, LHFI for information regarding the impact of COVID-19 on Trustmark’s loan portfolio. Paycheck Protection Program (PPP) Loans On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act (the CARES Act), a stimulus package intended to provide relief to businesses and consumers in the United States struggling as a result of the pandemic, was signed into law. A provision in the CARES Act included a $349 billion fund for the creation of the Paycheck Protection Program (PPP) through the Small Business Administration (SBA) and Treasury Department. The PPP is intended to provide loans to small businesses to pay their employees, rent, mortgage interest and utilities. PPP loans are forgivable, in whole or in part, if the proceeds are used for payroll and other permitted purposes in accordance with the requirements of the PPP. If not forgiven, in whole or in part, these loans carry a fixed rate of 1.00% per annum with payments deferred until the date the SBA remits the borrower’s loan forgiveness amount to the lender (or, if the borrower does not apply for loan forgiveness, ten months after the end of the borrower’s loan forgiveness covered period). Originally, the loans carried a term of two years under SBA rules implemented by the CARES Act, but a June 5, 2020 amendment to the CARES Act provided for a five-year minimum loan term for loans made beginning as of such date, and permitted lenders and borrowers to mutually agree to amend existing two-year loans to have terms of five years. The loans are 100% guaranteed by the SBA. The SBA pays the originating bank a processing fee ranging from 1.0% to 5.0%, based on the size of the loan. The SBA stopped accepting applications for PPP loans on August 8, 2020. At September 30, 2020, Trustmark had outstanding 9,691 PPP loans totaling $944.3 million (net of $25.7 million of deferred fees and costs). Due to amount and nature of the PPP loans, these loans were not included in the LHFI portfolio and are presented separately in the accompanying consolidated balance sheet. The PPP loans are fully guaranteed by the SBA; therefore, no ACL was estimated for these loans. Goodwill Impairment Evaluation Trustmark tests goodwill for impairment at least annually and, more frequently, if events or changes in circumstances indicate that it is more likely than not that there is possible impairment. Considering the significant negative impact that the ongoing COVID-19 pandemic is having on the U.S. economy, Trustmark has determined that the COVID-19 pandemic represented a triggering event prompting an evaluation of goodwill impairment. Based on the qualitative evaluation performed, Trustmark concluded that goodwill was not more than likely impaired at September 30, 2020. However, in light of the on-going impact of the COVID-19 pandemic, Trustmark will continue to monitor its goodwill for possible impairment.

Business, Basis of Financial Statement Presentation and Principles of Consolidation

9 Months Ended

Sep. 30, 2020

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Business, Basis of Financial Statement Presentation and Principles of Consolidation

Note 1 – Business, Basis of Financial Statement Presentation and Principles of Consolidation

Trustmark Corporation (Trustmark) is a bank holding company headquartered in Jackson, Mississippi. Through its subsidiaries, Trustmark operates as a financial services organization providing banking and financial solutions to corporate institutions and individual customers through 187 offices at September 30, 2020 in Alabama, Florida, Mississippi, Tennessee and Texas.

The consolidated financial statements include the accounts of Trustmark and all other entities in which Trustmark has a controlling financial interest. All significant intercompany accounts and transactions have been eliminated in consolidation. Certain reclassifications have been made to prior period amounts to conform to the current period presentation.

The accompanying unaudited condensed consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles (GAAP) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the consolidated financial statements, and notes thereto, included in Trustmark’s Annual Report on Form 10-K for its fiscal year ended December 31, 2019 (2019 Annual Report).

Operating results for the interim periods disclosed herein are not necessarily indicative of the results that may be expected for a full year or any future period. In the opinion of Management, all adjustments (consisting of normal recurring accruals) considered necessary for the fair presentation of these consolidated financial statements have been included. The preparation of financial statements in conformity with these accounting principles requires Management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements and income and expense during the reporting periods and the related disclosures. Although Management’s estimates contemplate current conditions and how they are expected to change in the future, it is reasonably possible that in 2020 actual conditions could vary from those anticipated, which could affect Trustmark’s financial condition and results of operations. Actual results could differ from those estimates.

Coronavirus 2019 (COVID-19) Pandemic

On March 11, 2020, the World Health Organization declared COVID-19, the disease caused by the novel coronavirus, a pandemic as a result of the global spread of the coronavirus illness. The COVID-19 pandemic has adversely affected, and may continue to adversely affect economic activity globally, nationally and locally. In response to the outbreak, federal and state authorities in the United States introduced various measures to try to limit or slow the spread of the virus, including travel restrictions, nonessential business closures, stay-at-home orders, and strict social distancing. The full impact of the COVID-19 pandemic is unknown and rapidly evolving. It has caused substantial disruption in international and U.S. economies, markets, and employment. The COVID-19 pandemic may continue to have a significant adverse impact on certain industries Trustmark serves, including restaurants and food services, hotels, retail and energy.

Because of the significant uncertainties related to the ultimate duration of the COVID-19 pandemic and its potential effects on customers and prospects, and on the national and local economy as a whole, there can be no assurances as to how the crisis may ultimately affect Trustmark’s loan portfolio. It is unknown how long the adverse conditions associated with the COVID-19 pandemic will last and what the complete financial effect will be to Trustmark. It is reasonably possible that estimates made in the financial statements could be materially and adversely impacted in the near term as a result of these conditions, including expected credit losses on loans and off-balance sheet credit exposures. See Note 3 – LHFI and Allowance for Credit Losses, LHFI for information regarding the impact of COVID-19 on Trustmark’s loan portfolio.

Paycheck Protection Program (PPP) Loans

On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act (the CARES Act), a stimulus package intended to provide relief to businesses and consumers in the United States struggling as a result of the pandemic, was signed into law. A provision in the CARES Act included a $349 billion fund for the creation of the Paycheck Protection Program (PPP) through the Small Business Administration (SBA) and Treasury Department. The PPP is intended to provide loans to small businesses to pay their employees, rent, mortgage interest and utilities. PPP loans are forgivable, in whole or in part, if the proceeds are used for payroll and other permitted purposes in accordance with the requirements of the PPP. If not forgiven, in whole or in part, these loans carry a fixed rate of 1.00% per annum with payments deferred until the date the SBA remits the borrower’s loan forgiveness amount to the lender (or, if the borrower does not apply for loan forgiveness, ten months after the end of the borrower’s loan forgiveness covered

period). Originally, the loans carried a term of two years under SBA rules implemented by the CARES Act, but a June 5, 2020 amendment to the CARES Act provided for a five-year minimum loan term for loans made beginning as of such date, and permitted lenders and borrowers to mutually agree to amend existing two-year loans to have terms of five years. The loans are 100% guaranteed by the SBA. The SBA pays the originating bank a processing fee ranging from 1.0% to 5.0%, based on the size of the loan. The SBA stopped accepting applications for PPP loans on August 8, 2020.

At September 30, 2020, Trustmark had outstanding 9,691 PPP loans totaling $944.3 million (net of $25.7 million of deferred fees and costs). Due to amount and nature of the PPP loans, these loans were not included in the LHFI portfolio and are presented separately in the accompanying consolidated balance sheet. The PPP loans are fully guaranteed by the SBA; therefore, no ACL was estimated for these loans.

Goodwill Impairment Evaluation

Trustmark tests goodwill for impairment at least annually and, more frequently, if events or changes in circumstances indicate that it is more likely than not that there is possible impairment. Considering the significant negative impact that the ongoing COVID-19 pandemic is having on the U.S. economy, Trustmark has determined that the COVID-19 pandemic represented a triggering event prompting an evaluation of goodwill impairment. Based on the qualitative evaluation performed, Trustmark concluded that goodwill was not more than likely impaired at September 30, 2020. However, in light of the on-going impact of the COVID-19 pandemic, Trustmark will continue to monitor its goodwill for possible impairment.