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LHFI and ACL, LHFI - Summary of Trustmark's Portfolio Segments, Loan Classes, Loan Pools and the ACL Methodology and Loss Drivers (Details) | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2025 | Dec. 31, 2024
Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | 1 -4 Family Residential Construction [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | BBB 7-10 US CBI (1), National Unemployment | BBB 7-10 US CBI (1), National Unemployment | [1]
Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | Lots and Development [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National HPI, National Unemployment | National HPI, National Unemployment |
Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | Unimproved Land [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National HPI, National Unemployment | National HPI, National Unemployment |
Loans Secured by Real Estate [Member] | Construction, Land Development and Other Land [Member] | All Other Consumer [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National HPI, National Unemployment | National HPI, National Unemployment |
Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | All Other Consumer [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National HPI, National Unemployment | National HPI, National Unemployment |
Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | Consumer 1-4 Family - 1st Liens [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National HPI, Southern Unemployment | National HPI, Southern Unemployment | [2]
Loans Secured by Real Estate [Member] | Other Secured by 1-4 Family Residential Properties [Member] | Nonresidential Owner- Occupied [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | Southern Unemployment, National CRE Price Index | Southern Unemployment, National CRE Price Index |
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Nonresidential Owner- Occupied [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | Southern Unemployment, National CRE Price Index | Southern Unemployment, National CRE Price Index |
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Nonowner-Occupied - Hotel/Motel [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National CRE Price Index, Southern Unemployment | National CRE Price Index, Southern Unemployment |
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Nonowner-Occupied - Office [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National CRE Price Index, Southern Unemployment | National CRE Price Index, Southern Unemployment |
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Nonowner-Occupied- Retail [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National CRE Price Index, Southern Unemployment | National CRE Price Index, Southern Unemployment |
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Nonowner-Occupied- Senior Living/ Nursing Homes [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National CRE Price Index, Southern Unemployment | National CRE Price Index, Southern Unemployment |
Loans Secured by Real Estate [Member] | Secured by Nonfarm, Nonresidential Properties [Member] | Nonowner-occupied - All Other [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National CRE Price Index, Southern Unemployment | National CRE Price Index, Southern Unemployment |
Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member] | Nonresidential Owner- Occupied [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | Southern Unemployment, National CRE Price Index | Southern Unemployment, National CRE Price Index |
Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member] | Nonowner-occupied - All Other [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National CRE Price Index, Southern Unemployment | National CRE Price Index, Southern Unemployment |
Loans Secured by Real Estate [Member] | Other Real Estate Secured [Member] | Nonresidential Nonowner- Occupied - Apartments [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National CRE Price Index, Southern Unemployment | National CRE Price Index, Southern Unemployment |
Commercial and Industrial Loans [Member] | Commercial and Industrial Loans [Member] | Commercial and Industrial - Non-Working Capital [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | Trustmark historical data | Trustmark historical data |
Commercial and Industrial Loans [Member] | Commercial and Industrial Loans [Member] | Commercial and Industrial - Working Capital [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | Trustmark historical data | Trustmark historical data |
Commercial and Industrial Loans [Member] | Commercial and Industrial Loans [Member] | Equipment Finance Loans [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | WARM | WARM |
Loss Drivers | Southern Unemployment, National GDP | Southern Unemployment, National GDP |
Commercial and Industrial Loans [Member] | Commercial and Industrial Loans [Member] | Credit Cards [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | WARM | WARM |
Loss Drivers | Trustmark call report data | Trustmark call report data |
Other Loans Secured by Real Estate [Member] | Other Construction [Member] | Other Construction [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National CRE Price Index, National Unemployment, BBB 7-10 US CBI | National CRE Price Index, National Unemployment, BBB 7-10 US CBI |
Other Loans Secured by Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member] | Trustmark Mortgage [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | WARM | WARM |
Loss Drivers | Southern Unemployment | Southern Unemployment |
Consumer Loans [Member] | Consumer Loans [Member] | All Other Consumer [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | National HPI, National Unemployment | National HPI, National Unemployment |
Consumer Loans [Member] | Consumer Loans [Member] | Credit Cards [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | WARM | WARM |
Loss Drivers | Trustmark call report data | Trustmark call report data |
Consumer Loans [Member] | Consumer Loans [Member] | Overdrafts [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | Loss Rate | Loss Rate |
Loss Drivers | Trustmark historical data | Trustmark historical data |
State and Other Political Subdivision Loans [Member] | State and Other Political Subdivision Loans [Member] | Obligations of State and Political Subdivisions [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | Moody's Bond Default Study | Moody's Bond Default Study |
Other Commercial Loans and Leases [Member] | Other Commercial Loans And Leases [Member] | Commercial and Industrial - Non-Working Capital [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | Trustmark historical data | Trustmark historical data |
Other Commercial Loans and Leases [Member] | Other Commercial Loans And Leases [Member] | Commercial and Industrial - Working Capital [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | Trustmark historical data | Trustmark historical data |
Other Commercial Loans and Leases [Member] | Other Commercial Loans And Leases [Member] | Equipment Finance Leases [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | WARM | WARM |
Loss Drivers | Southern Unemployment, National GDP | Southern Unemployment, National GDP |
Other Commercial Loans and Leases [Member] | Other Commercial Loans And Leases [Member] | Other Loans [Member] |  |  |
Financing Receivable Recorded Investment [Line Items] |  |  |
Methodology | DCF | DCF |
Loss Drivers | BBB 7-10 US CBI, Southern Unemployment | BBB 7-10 US CBI, Southern Unemployment |
[1] | Loss driver was National HPI at December 31, 2024
[2] | Loss driver was National Unemployement at December 31, 2024.

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