XML 27 R73.htm IDEA: XBRL DOCUMENT v2.4.1.9
Acquired Loans Part 6 (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2014
Dec. 31, 2013
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days $ 3,823trmk_AcquiredLoans30To59DaysPastDue $ 12,600trmk_AcquiredLoans30To59DaysPastDue
Past Due 60 - 89 Days 2,794trmk_AcquiredLoans60To89DaysPastDue 7,171trmk_AcquiredLoans60To89DaysPastDue
Past Due Greater Than 90 Days 43,412trmk_AcquiredLoansMoreThan90DaysPastDue [1] 63,444trmk_AcquiredLoansMoreThan90DaysPastDue [1]
Total Past Due 50,029trmk_AcquiredLoansCarryingValueTotalPastDue 83,215trmk_AcquiredLoansCarryingValueTotalPastDue
Nonaccrual 1,144trmk_AcquiredLoansNonaccrualStatus [2] 2,353trmk_AcquiredLoansNonaccrualStatus [2]
Current Loans 498,236trmk_AcquiredLoansRecordedInvestmentCurrent 718,638trmk_AcquiredLoansRecordedInvestmentCurrent
Acquired loans 549,409trmk_AcquiredLoansCarryingValueLoans 804,206trmk_AcquiredLoansCarryingValueLoans
Noncovered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 3,331trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
11,171trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
Past Due 60 - 89 Days 2,010trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
5,012trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
Past Due Greater Than 90 Days 42,149trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
[1] 60,308trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
[1]
Total Past Due 47,490trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
76,491trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
Nonaccrual 1,077trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
[2] 1,867trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
[2]
Current Loans 477,216trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
691,632trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
Acquired loans 525,783trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
769,990trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
Covered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 492trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
1,429trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
Past Due 60 - 89 Days 784trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
2,159trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
Past Due Greater Than 90 Days 1,263trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
[1] 3,136trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
[1]
Total Past Due 2,539trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
6,724trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
Nonaccrual 67trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
[2] 486trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
[2]
Current Loans 21,020trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
27,006trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
Acquired loans 23,626trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
34,216trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
Real Estate Secured Financing Receivable [Member] | Construction Land Development And Other Financing Receivable [Member] | Noncovered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 246trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
1,648trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due 60 - 89 Days 7trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
468trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due Greater Than 90 Days 21,985trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1] 31,744trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1]
Total Past Due 22,238trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
33,860trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Nonaccrual 194trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2] 67trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2]
Current Loans 35,877trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
65,001trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Acquired loans 58,309trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
98,928trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Real Estate Secured Financing Receivable [Member] | Construction Land Development And Other Financing Receivable [Member] | Covered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 0trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
87trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due 60 - 89 Days 0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due Greater Than 90 Days 376trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1] 553trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1]
Total Past Due 376trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
640trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Nonaccrual 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2] 445trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2]
Current Loans 821trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
1,278trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Acquired loans 1,197trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
2,363trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ConstructionLandDevelopmentAndOtherFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Real Estate Secured Financing Receivable [Member] | Secured by 1-4 Family Residential Properties [Member] | Noncovered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 2,576trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
3,901trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due 60 - 89 Days 981trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
1,166trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due Greater Than 90 Days 5,162trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1] 7,589trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1]
Total Past Due 8,719trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
12,656trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Nonaccrual 422trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2] 116trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2]
Current Loans 107,779trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
145,142trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Acquired loans 116,920trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
157,914trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Real Estate Secured Financing Receivable [Member] | Secured by 1-4 Family Residential Properties [Member] | Covered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 253trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
515trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due 60 - 89 Days 296trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
358trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due Greater Than 90 Days 477trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1] 1,142trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1]
Total Past Due 1,026trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
2,015trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Nonaccrual 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2] 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2]
Current Loans 12,154trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
14,401trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Acquired loans 13,180trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
16,416trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_ResidentialFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Real Estate Secured Financing Receivable [Member] | Nonfarm, Nonresidential Properties [Member] | Noncovered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 89trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
4,851trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due 60 - 89 Days 865trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
3,127trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due Greater Than 90 Days 13,275trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1] 15,421trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1]
Total Past Due 14,229trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
23,399trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Nonaccrual 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2] 461trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2]
Current Loans 188,094trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
263,276trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Acquired loans 202,323trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
287,136trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Real Estate Secured Financing Receivable [Member] | Nonfarm, Nonresidential Properties [Member] | Covered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 239trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
243trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due 60 - 89 Days 488trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
1,662trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due Greater Than 90 Days 0trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1] 793trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1]
Total Past Due 727trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
2,698trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Nonaccrual 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2] 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2]
Current Loans 6,945trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
8,247trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Acquired loans 7,672trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
10,945trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_NonresidentialPropertiesFinancingReceivablesMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Real Estate Secured Financing Receivable [Member] | Other Real Estate Secured Financing Receivable [Member] | Noncovered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 0trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
40trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due 60 - 89 Days 0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due Greater Than 90 Days 604trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1] 1,922trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1]
Total Past Due 604trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
1,962trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Nonaccrual 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2] 33trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2]
Current Loans 27,209trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
31,953trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Acquired loans 27,813trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
33,948trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Real Estate Secured Financing Receivable [Member] | Other Real Estate Secured Financing Receivable [Member] | Covered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 0trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
571trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due 60 - 89 Days 0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
139trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Past Due Greater Than 90 Days 368trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1] 2trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[1]
Total Past Due 368trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
712trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Nonaccrual 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2] 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
[2]
Current Loans 728trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
1,932trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Acquired loans 1,096trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
2,644trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableBySubClassReceivableAxis
= trmk_OtherRealEstateSecuredFinancingReceivableMember
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_RealEstateSecuredFinancingReceivableMember
Commercial And Industrial Loans Financing Receivable [Member] | Noncovered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 334trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
526trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
Past Due 60 - 89 Days 128trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
217trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
Past Due Greater Than 90 Days 1,099trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
[1] 3,387trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
[1]
Total Past Due 1,561trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
4,130trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
Nonaccrual 461trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
[2] 1,170trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
[2]
Current Loans 86,234trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
144,195trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
Acquired loans 88,256trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
149,495trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
Commercial And Industrial Loans Financing Receivable [Member] | Covered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 0trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
13trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
Past Due 60 - 89 Days 0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
Past Due Greater Than 90 Days 42trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
[1] 0trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
[1]
Total Past Due 42trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
13trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
Nonaccrual 67trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
[2] 41trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
[2]
Current Loans 168trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
340trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
Acquired loans 277trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
394trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_CommercialAndIndustrialLoansFinancingReceivableMember
Consumer Loans Financing Receivable [Member] | Noncovered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 86trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
205trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
Past Due 60 - 89 Days 29trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
34trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
Past Due Greater Than 90 Days 24trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
[1] 92trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
[1]
Total Past Due 139trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
331trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
Nonaccrual 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
[2] 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
[2]
Current Loans 9,633trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
18,097trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
Acquired loans 9,772trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
18,428trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
Consumer Loans Financing Receivable [Member] | Covered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 0trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
0trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
Past Due 60 - 89 Days 0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
Past Due Greater Than 90 Days 0trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
[1] 0trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
[1]
Total Past Due 0trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
0trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
Nonaccrual 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
[2] 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
[2]
Current Loans 0trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
119trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
Acquired loans 0trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
119trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_ConsumerLoansFinancingReceivableMember
Other Loans Financing Receivable [Member] | Noncovered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 0trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
0trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
Past Due 60 - 89 Days 0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
Past Due Greater Than 90 Days 0trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
[1] 153trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
[1]
Total Past Due 0trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
153trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
Nonaccrual 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
[2] 20trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
[2]
Current Loans 22,390trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
23,968trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
Acquired loans 22,390trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
24,141trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_NoncoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
Other Loans Financing Receivable [Member] | Covered [Member]    
Acquired Loans, Aging [Abstract]    
Past Due 30 - 59 Days 0trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
0trmk_AcquiredLoans30To59DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
Past Due 60 - 89 Days 0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
0trmk_AcquiredLoans60To89DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
Past Due Greater Than 90 Days 0trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
[1] 646trmk_AcquiredLoansMoreThan90DaysPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
[1]
Total Past Due 0trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
646trmk_AcquiredLoansCarryingValueTotalPastDue
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
Nonaccrual 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
[2] 0trmk_AcquiredLoansNonaccrualStatus
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
[2]
Current Loans 204trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
689trmk_AcquiredLoansRecordedInvestmentCurrent
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
Acquired loans $ 204trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
$ 1,335trmk_AcquiredLoansCarryingValueLoans
/ trmk_FinancingReceivableByTypeAxis
= trmk_CoveredMember
/ us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis
= trmk_OtherLoansFinancingReceivableMember
[1] Past due 90 days or more but still accruing interest.
[2] Acquired loans not accounted for under FASB ASC Topic 310-30.