XML 96 R85.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Defined Benefit and Other Postretirement Benefits (Details) (USD $) | 12 Months Ended
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Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Trustmark Capital Accumulation Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Years of service required to vest | 3 years |  |
Change in benefit obligation [Roll Forward] |  |  |
Benefit obligation, beginning of year | $ 128,974,000 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | $ 103,235,000 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Benefit obligation from business combination | 0 us-gaap_DefinedBenefitPlanBusinessCombinationsAndAcquisitionsBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 43,138,000 us-gaap_DefinedBenefitPlanBusinessCombinationsAndAcquisitionsBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Service cost | 495,000 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 595,000 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 547,000 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Interest cost | 5,299,000 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 4,758,000 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 3,942,000 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Actuarial loss (gain) | 11,675,000 trmk_PensionAndOtherPostretirementBenefitPlansActuarialLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | (8,060,000)trmk_PensionAndOtherPostretirementBenefitPlansActuarialLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Benefits paid | (7,041,000)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | (14,692,000)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Settlement loss from BancTrust termination | 1,355,000 trmk_SettlementLossFromBancTrustTermination / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 0 trmk_SettlementLossFromBancTrustTermination / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Benefit obligation, end of year | 101,904,000 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 128,974,000 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 103,235,000 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, beginning of year | 126,142,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 76,660,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Fair value of plan assets from business combination | 0 us-gaap_DefinedBenefitPlanBusinessCombinationsAndAcquisitionsPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 40,391,000 us-gaap_DefinedBenefitPlanBusinessCombinationsAndAcquisitionsPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Actual return on plan assets | 4,632,000 us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 21,661,000 us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Employer contributions | 1,407,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 2,122,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Benefit payments | (7,041,000)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | (14,692,000)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Fair value of plan assets, end of year | 86,287,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 126,142,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 76,660,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Funded status at end of year - net liability | (15,617,000)us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | (2,832,000)us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Balance, end of period | 86,287,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 126,142,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 76,660,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Amounts recognized in accumulated other comprehensive income (loss) [Abstract] |  |  |
Net loss | 28,100,000 us-gaap_AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 15,436,000 us-gaap_AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Net periodic benefit cost [Abstract] |  |  |
Service cost | 495,000 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 595,000 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 547,000 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Interest cost | 5,299,000 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 4,758,000 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 3,942,000 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Expected return on plan assets | (6,245,000)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | (7,720,000)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | (5,983,000)us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Recognized net loss due to BancTrust termination | 1,355,000 trmk_RecognizedNetGainLossDueToBancTrustTermination / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 0 trmk_RecognizedNetGainLossDueToBancTrustTermination / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 0 trmk_RecognizedNetGainLossDueToBancTrustTermination / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Recognized net loss due to lump sum settlements | 905,000 us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1 / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 2,225,000 us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1 / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanRecognizedNetGainLossDueToSettlements1 / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Recognized net actuarial (gain) loss | (283,000)us-gaap_DefinedBenefitPlanActuarialGainLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 5,516,000 us-gaap_DefinedBenefitPlanActuarialGainLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 5,225,000 us-gaap_DefinedBenefitPlanActuarialGainLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Net periodic benefit cost | 1,526,000 us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 5,374,000 us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 3,731,000 us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Other changes in plan assets and benefit obligation recognized in other comprehensive (loss), before taxes [Abstract] |  |  |
Total recognized in other comprehensive income (loss) | 12,664,000 us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetGainLossBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | (29,742,000)us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetGainLossBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | (3,861,000)us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetGainLossBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Total recognized in net periodic benefit cost and other comprehensive income (loss) | 14,190,000 trmk_DefinedBenefitPlanTotalRecognizedInNetPeriodicBenefitCostAndOtherComprehensiveLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | (24,368,000)trmk_DefinedBenefitPlanTotalRecognizedInNetPeriodicBenefitCostAndOtherComprehensiveLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | (130,000)trmk_DefinedBenefitPlanTotalRecognizedInNetPeriodicBenefitCostAndOtherComprehensiveLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Weighted-average assumptions as of end of year [Abstract] |  |  |
Discount rate for benefit obligation (in hundredths) | 3.57%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 4.30%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 3.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Discount rate for net periodic benefit cost (in hundredths) | 4.30%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 3.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Expected long-term return on plan assets (in hundredths) | 7.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 7.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 8.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Asset target allocations [Abstract] |  |  |
Weighted-average asset allocation (in hundredths) | 100.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 100.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Fair value of plan assets | 86,287,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 126,142,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 76,660,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Contributions [Abstract] |  |  |
Expected minimum required contribution, Prior to HAFTA | 1,800,000 trmk_DefinedBenefitPlanPreviousMinimumEmployerContribution / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 2,100,000 trmk_DefinedBenefitPlanPreviousMinimumEmployerContribution / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Expected minimum required contribution in the next fiscal year | 0 trmk_DefinedBenefitPlanMinimumEmployerContributionNextFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Expected minimum required contribution, after HAFTA | 0 us-gaap_DefinedBenefitPlansEstimatedFutureEmployerContributionsInNextFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Actual contribution | 1,000,000 us-gaap_DefinedBenefitPlanContributionsByPlanParticipants / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Estimated future benefit payments [Abstract] |  |  |
2015 | 10,654,000 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
2016 | 8,402,000 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
2017 | 7,734,000 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
2018 | 6,346,000 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
2019 | 6,286,000 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
2020 - 2024 | 28,762,000 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Accumulated other comprehensive loss expected to be recognized during next fiscal year as components of net periodic benefit cost | (5,000,000)us-gaap_DefinedBenefitPlanAmountToBeAmortizedFromAccumulatedOtherComprehensiveIncomeLossNextFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Other Benefit Plans - Defined Contribution Plan [Abstract] |  |  |
Trustmarks contribution to defined contribution plan | 6,700,000 us-gaap_DefinedContributionPlanCostRecognized / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 6,800,000 us-gaap_DefinedContributionPlanCostRecognized / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 5,700,000 us-gaap_DefinedContributionPlanCostRecognized / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember
Trustmark contributions to the plan | 100.00%us-gaap_DefinedContributionPlanEmployersMatchingContributionAnnualVestingPercentage / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Contributions up to a maximum of eligible compensation | 6.00%us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Period when associates may become eligible to make elective deferral contributions after employment | 30 days |  |
Eligible associates must complete number of years of service | 1 year |  |
Trustmark Capital Accumulation Plan [Member] | Level 1 [ Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 86,133,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 118,999,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Balance, end of period | 86,133,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 118,999,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 86,133,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 118,999,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Trustmark Capital Accumulation Plan [Member] | Level 2 [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 6,980,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Balance, end of period | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 6,980,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 6,980,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Trustmark Capital Accumulation Plan [Member] | Level 3 [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 154,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 163,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Balance, end of period | 154,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 163,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 154,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 163,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Trustmark Capital Accumulation Plan [Member] | Money Market Funds [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 7,544,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 6,563,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Balance, end of period | 7,544,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 6,563,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Asset target allocations [Abstract] |  |  |
Weighted-average asset allocation (in hundredths) | 8.70%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 5.20%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Fair value of plan assets | 7,544,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 6,563,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Trustmark Capital Accumulation Plan [Member] | Money Market Funds [Member] | Level 1 [ Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 7,544,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 6,563,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Balance, end of period | 7,544,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 6,563,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 7,544,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 6,563,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Trustmark Capital Accumulation Plan [Member] | Money Market Funds [Member] | Level 2 [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Balance, end of period | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Trustmark Capital Accumulation Plan [Member] | Money Market Funds [Member] | Level 3 [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Balance, end of period | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_MoneyMarketFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Trustmark Capital Accumulation Plan [Member] | Fixed Income Mutual Funds [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 10,267,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 22,225,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Balance, end of period | 10,267,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 22,225,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Asset target allocations [Abstract] |  |  |
Weighted-average asset allocation (in hundredths) | 11.90%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 17.60%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Fair value of plan assets | 10,267,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 22,225,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Trustmark Capital Accumulation Plan [Member] | Fixed Income Mutual Funds [Member] | Level 1 [ Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 10,267,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 15,245,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Balance, end of period | 10,267,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 15,245,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 10,267,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 15,245,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Trustmark Capital Accumulation Plan [Member] | Fixed Income Mutual Funds [Member] | Level 2 [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 6,980,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Balance, end of period | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 6,980,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 6,980,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Trustmark Capital Accumulation Plan [Member] | Fixed Income Mutual Funds [Member] | Level 3 [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Balance, end of period | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = trmk_FixedIncomeMutualFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Trustmark Capital Accumulation Plan [Member] | Equity Mutual Funds [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 62,265,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 73,608,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Balance, end of period | 62,265,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 73,608,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Asset target allocations [Abstract] |  |  |
Weighted-average asset allocation (in hundredths) | 72.20%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 58.40%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Fair value of plan assets | 62,265,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 73,608,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Trustmark Capital Accumulation Plan [Member] | Equity Mutual Funds [Member] | Level 1 [ Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 62,265,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 73,608,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Balance, end of period | 62,265,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 73,608,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 62,265,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 73,608,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Trustmark Capital Accumulation Plan [Member] | Equity Mutual Funds [Member] | Level 2 [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Balance, end of period | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Trustmark Capital Accumulation Plan [Member] | Equity Mutual Funds [Member] | Level 3 [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Balance, end of period | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquityFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Trustmark Capital Accumulation Plan [Member] | Equity Securities [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 6,057,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 23,583,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Balance, end of period | 6,057,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 23,583,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Asset target allocations [Abstract] |  |  |
Weighted-average asset allocation (in hundredths) | 7.00%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 18.70%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Fair value of plan assets | 6,057,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 23,583,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Trustmark Capital Accumulation Plan [Member] | Equity Securities [Member] | Level 1 [ Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 6,057,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 23,583,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Balance, end of period | 6,057,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 23,583,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 6,057,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 23,583,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Trustmark Capital Accumulation Plan [Member] | Equity Securities [Member] | Level 2 [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Balance, end of period | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Trustmark Capital Accumulation Plan [Member] | Equity Securities [Member] | Level 3 [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Balance, end of period | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_EquitySecuritiesMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Trustmark Capital Accumulation Plan [Member] | Fixed Income Hedge Funds [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 154,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 163,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Balance, end of period | 154,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 163,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Asset target allocations [Abstract] |  |  |
Weighted-average asset allocation (in hundredths) | 0.20%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 0.10%us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Fair value of plan assets | 154,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember | 163,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |
Trustmark Capital Accumulation Plan [Member] | Fixed Income Hedge Funds [Member] | Level 1 [ Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Balance, end of period | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member |
Trustmark Capital Accumulation Plan [Member] | Fixed Income Hedge Funds [Member] | Level 2 [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, end of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Balance, end of period | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member |
Trustmark Capital Accumulation Plan [Member] | Fixed Income Hedge Funds [Member] | Level 3 [Member] |  |  |
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, beginning of year | 163,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 163,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Fair value of plan assets, end of year | 154,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 163,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Change in fair value | (9,000)us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsPeriodIncreaseDecrease / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssetsPeriodIncreaseDecrease / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Balance, end of period | 154,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 163,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 154,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member | 163,000 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_HedgeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel3Member |
Trustmark Capital Accumulation Plan [Member] | Cash and Cash Equivalents [Member] |  |  |
Asset target allocations [Abstract] |  |  |
Target asset allocation, minimum (in hundredths) | 0.00%trmk_DefinedBenefitPlanTargetAllocationPercentageOfAssetsRangeMinimum / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Target asset allocation, maximum (in hundredths) | 10.00%trmk_DefinedBenefitPlanTargetAllocationPercentageOfAssetsRangeMaximum / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_CashAndCashEquivalentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Trustmark Capital Accumulation Plan [Member] | Fixed Income Funds [Member] |  |  |
Asset target allocations [Abstract] |  |  |
Target asset allocation, minimum (in hundredths) | 10.00%trmk_DefinedBenefitPlanTargetAllocationPercentageOfAssetsRangeMinimum / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Target asset allocation, maximum (in hundredths) | 30.00%trmk_DefinedBenefitPlanTargetAllocationPercentageOfAssetsRangeMaximum / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_FixedIncomeFundsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Trustmark Capital Accumulation Plan [Member] | Domestic Equity [Member] |  |  |
Asset target allocations [Abstract] |  |  |
Target asset allocation, minimum (in hundredths) | 30.00%trmk_DefinedBenefitPlanTargetAllocationPercentageOfAssetsRangeMinimum / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_PrivateEquityFundsDomesticMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Target asset allocation, maximum (in hundredths) | 55.00%trmk_DefinedBenefitPlanTargetAllocationPercentageOfAssetsRangeMaximum / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_PrivateEquityFundsDomesticMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Trustmark Capital Accumulation Plan [Member] | International Equity [Member] |  |  |
Asset target allocations [Abstract] |  |  |
Target asset allocation, minimum (in hundredths) | 10.00%trmk_DefinedBenefitPlanTargetAllocationPercentageOfAssetsRangeMinimum / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_PrivateEquityFundsForeignMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Target asset allocation, maximum (in hundredths) | 30.00%trmk_DefinedBenefitPlanTargetAllocationPercentageOfAssetsRangeMaximum / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_PrivateEquityFundsForeignMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Trustmark Capital Accumulation Plan [Member] | Other Investments [Member] |  |  |
Asset target allocations [Abstract] |  |  |
Target asset allocation, minimum (in hundredths) | 0.00%trmk_DefinedBenefitPlanTargetAllocationPercentageOfAssetsRangeMinimum / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_OtherInvestmentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Target asset allocation, maximum (in hundredths) | 20.00%trmk_DefinedBenefitPlanTargetAllocationPercentageOfAssetsRangeMaximum / us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis = us-gaap_OtherInvestmentsMember / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_PensionPlansDefinedBenefitMember |  |
Supplemental Retirement Plans [Member] |  |  |
Change in benefit obligation [Roll Forward] |  |  |
Benefit obligation, beginning of year | 52,489,000 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 56,619,000 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |
Benefit obligation from business combination | 0 us-gaap_DefinedBenefitPlanBusinessCombinationsAndAcquisitionsBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 1,658,000 us-gaap_DefinedBenefitPlanBusinessCombinationsAndAcquisitionsBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |
Service cost | 296,000 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 597,000 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 679,000 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Interest cost | 2,198,000 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 1,943,000 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 2,067,000 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Actuarial loss (gain) | 7,392,000 trmk_PensionAndOtherPostretirementBenefitPlansActuarialLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | (4,187,000)trmk_PensionAndOtherPostretirementBenefitPlansActuarialLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |
Benefits paid | (2,631,000)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | (4,141,000)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |
Prior service cost due to amendment | 0 us-gaap_DefinedBenefitPlanPlanAmendments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanPlanAmendments / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |
Benefit obligation, end of year | 59,744,000 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 52,489,000 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 56,619,000 us-gaap_DefinedBenefitPlanBenefitObligation / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Change in plan assets [ Roll Forward] |  |  |
Fair value of plan assets, beginning of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |
Employer contributions | 2,631,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 4,141,000 us-gaap_DefinedBenefitPlanContributionsByEmployer / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |
Benefit payments | (2,631,000)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | (4,141,000)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |
Fair value of plan assets, end of year | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Funded status at end of year - net liability | (59,744,000)us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | (52,489,000)us-gaap_DefinedBenefitPlanFundedStatusOfPlan / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |
Balance, end of period | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Amounts recognized in accumulated other comprehensive income (loss) [Abstract] |  |  |
Net loss | 21,242,000 us-gaap_AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 14,509,000 us-gaap_AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |
Prior service cost | 1,860,000 us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 2,110,000 us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |
Amounts recognized | 23,102,000 us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 16,619,000 us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |
Net periodic benefit cost [Abstract] |  |  |
Service cost | 296,000 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 597,000 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 679,000 us-gaap_DefinedBenefitPlanServiceCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Interest cost | 2,198,000 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 1,943,000 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 2,067,000 us-gaap_DefinedBenefitPlanInterestCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Amortization of prior service credits | 250,000 us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 250,000 us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 250,000 us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Recognized net actuarial (gain) loss | 661,000 us-gaap_DefinedBenefitPlanActuarialGainLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 1,038,000 us-gaap_DefinedBenefitPlanActuarialGainLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 861,000 us-gaap_DefinedBenefitPlanActuarialGainLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Net periodic benefit cost | 3,405,000 us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 3,828,000 us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 3,857,000 us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Other changes in plan assets and benefit obligation recognized in other comprehensive (loss), before taxes [Abstract] |  |  |
Net (gain) loss | 6,733,000 us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | (5,224,000)us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 2,507,000 us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Prior service cost | 0 us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 198,000 us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeNetPriorServiceCostCreditBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Amortization of prior service cost | (250,000)us-gaap_DefinedBenefitPlanFutureAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | (250,000)us-gaap_DefinedBenefitPlanFutureAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | (250,000)us-gaap_DefinedBenefitPlanFutureAmortizationOfPriorServiceCostCredit / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Total recognized in other comprehensive income (loss) | 6,483,000 us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetGainLossBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | (5,474,000)us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetGainLossBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 2,455,000 us-gaap_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetGainLossBeforeTax / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Total recognized in net periodic benefit cost and other comprehensive income (loss) | 9,888,000 trmk_DefinedBenefitPlanTotalRecognizedInNetPeriodicBenefitCostAndOtherComprehensiveLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | (1,646,000)trmk_DefinedBenefitPlanTotalRecognizedInNetPeriodicBenefitCostAndOtherComprehensiveLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 6,312,000 trmk_DefinedBenefitPlanTotalRecognizedInNetPeriodicBenefitCostAndOtherComprehensiveLoss / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Weighted-average assumptions as of end of year [Abstract] |  |  |
Discount rate for benefit obligation (in hundredths) | 3.57%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 4.30%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 3.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Discount rate for net periodic benefit cost (in hundredths) | 4.30%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 3.50%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 4.00%us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Asset target allocations [Abstract] |  |  |
Fair value of plan assets | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember | 0 us-gaap_DefinedBenefitPlanFairValueOfPlanAssets / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember
Estimated future benefit payments [Abstract] |  |  |
2015 | 2,868,000 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |  |
2016 | 3,145,000 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |  |
2017 | 3,479,000 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |  |
2018 | 3,591,000 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |  |
2019 | 3,656,000 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |  |
2020 - 2024 | 19,504,000 us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |  |
Accumulated other comprehensive loss expected to be recognized during next fiscal year as components of net periodic benefit cost | (992,000)us-gaap_DefinedBenefitPlanAmountToBeAmortizedFromAccumulatedOtherComprehensiveIncomeLossNextFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |  |
Accumulated other comprehensive loss expected to be recognized during next fiscal year as prior service cost | 250,000 trmk_PensionAndOtherPostretirementBenefitPlansPriorServiceCostToBeRecognizedDuringNextFiscalYear / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = us-gaap_OtherPensionPlansPostretirementOrSupplementalPlansDefinedBenefitMember |  |
BancTrust Pension Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pre-tax gain recognized in OCI as a result of the termination of the plan | 1,200,000 trmk_DefinedBenefitPlanAmountsRecognizedInOtherComprehensiveIncomeLossNetActuarialGainLossBeforeTaxAttributableToAcquisition / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = trmk_BanctrustPensionPlanMember |  |
Change in benefit obligation [Roll Forward] |  |  |
Benefits paid | (38,853,000)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = trmk_BanctrustPensionPlanMember | 0 us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = trmk_BanctrustPensionPlanMember |
Change in plan assets [ Roll Forward] |  |  |
Benefit payments | (38,853,000)us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = trmk_BanctrustPensionPlanMember | 0 us-gaap_DefinedBenefitPlanBenefitsPaid / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = trmk_BanctrustPensionPlanMember |
Other Benefit Plans - Defined Contribution Plan [Abstract] |  |  |
Contribution to complete the plan termination | $ 334,000 us-gaap_DefinedBenefitPlanSpecialTerminationBenefits / us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis = trmk_BanctrustPensionPlanMember |  |

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- Definition 1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Projected Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6522206 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Postretirement Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503904 + Details
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- Definition The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Postretirement Benefits -URI http://asc.fasb.org/extlink&oid=6521376 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Benefits -URI http://asc.fasb.org/extlink&oid=6506267 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Benefits -URI http://asc.fasb.org/extlink&oid=6506309 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(6) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(5) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The amount of increase in the benefit obligation attributed to business combinations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(8) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The amount of increase in the plan assets attributed to a business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(6) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The increase in the fair value of plan assets from contributions made by the employer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The amount of contributions made by plan participants. This item represents a periodic increase to the plan obligation and an increase to plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Expected Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512136 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Expected Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512171 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(3) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 50 -URI http://asc.fasb.org/extlink&oid=29635418&loc=d3e12355-114930 + Details
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- Definition The amount of increase or decrease in the fair value of plan assets during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=21915240&loc=d3e1703-114919 + Details
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- Definition Amount included in accumulated other comprehensive income (AOCI) related to prior service cost (credit) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position. + References No definition available. + Details
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- Definition The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(2) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The amount of increase or decrease due to a change in the terms of an existing plan or the initiation of a new plan. A plan amendment may increase or decrease benefits, including those attributed to years of service already rendered. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Glossary Plan Amendment -URI http://asc.fasb.org/extlink&oid=6520743 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Plan Amendment -URI http://asc.fasb.org/extlink&oid=6520782 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(7) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Amount of net gain (loss) recognized in net periodic benefit cost as a result of an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include, but are not limited to, lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contracts to cover vested benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 15 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(1) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Service Cost (Component of Net Periodic Pension Cost) -URI http://asc.fasb.org/extlink&oid=6525008 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The amount of increase related to special termination benefits offered to and accepted by employees in connection with their termination of employment that are only offered for a short period of time. A situation involving termination benefits may also involve a curtailment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(10) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Termination Benefits -URI http://asc.fasb.org/extlink&oid=6526498 + Details
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- Definition Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942 + Details
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- Definition Percentage of employer's matching contributions to a defined contribution plan that vests in a given year. + References No definition available. + Details
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- Definition Amount before tax of reclassification adjustment from accumulated other comprehensive income (loss) for actuarial gain (loss) related to pension and other postretirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e637-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e689-108580 + Details
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