XML 64 R27.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Allowance for Loan Losses (Details 2) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2015 | Mar. 31, 2014 | Dec. 31, 2014
Unpaid Principal Balance |  |  |
TOTAL | $ 16,658 us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance |  | $ 16,394 us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
Recorded Investment |  |  |
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 12,787 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment |  | 11,477 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
Fair value | 14,851 us-gaap_ImpairedFinancingReceivableRecordedInvestment |  | 14,606 us-gaap_ImpairedFinancingReceivableRecordedInvestment
Allowance For Loan Losses Allocated |  |  |
TOTAL | 1,557 thff_ImpairedFinancingReceivableLoanLossesAlocated |  | 1,911 thff_ImpairedFinancingReceivableLoanLossesAlocated
Average Recorded Investment |  |  |
TOTAL | 14,730 us-gaap_ImpairedFinancingReceivableAverageRecordedInvestment | 17,918 us-gaap_ImpairedFinancingReceivableAverageRecordedInvestment | 16,732 us-gaap_ImpairedFinancingReceivableAverageRecordedInvestment
Interest Income Recognized |  |  |
TOTAL | 0 us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethod | 0 us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethod | 0 us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethod
Cash Basis Interest Income Recognized |  |  |
TOTAL | 0 us-gaap_ImpairedFinancingReceivableInterestIncomeCashBasisMethod | 0 us-gaap_ImpairedFinancingReceivableInterestIncomeCashBasisMethod | 0 us-gaap_ImpairedFinancingReceivableInterestIncomeCashBasisMethod
Commercial & Industrial |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded: | 251 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember |  | 1,200 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
With an allowance recorded: | 8,824 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember |  | 7,388 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
Recorded Investment |  |  |
With no related allowance recorded: | 251 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember |  | 926 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 7,017 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember |  | 5,874 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
Fair value | 6,442 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember |  | 4,818 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
Allowance For Loan Losses Allocated |  |  |
With no related allowance recorded: | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember |  | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
With an allowance recorded: | 575 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember |  | 1,056 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
Average Recorded Investment |  |  |
With no related allowance recorded: | 589 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember | 1,906 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember | 2,589 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
With an allowance recorded: | 6,446 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember | 8,085 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember | 6,177 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
Cash Basis Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_CommercialAndIndustrialReceivablesMember
Farmland |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
Fair value | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember |  | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
Allowance For Loan Losses Allocated |  |  |
With no related allowance recorded: | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember |  | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
With an allowance recorded: | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember |  | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
Average Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
Cash Basis Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_FarmlandMember
Non Farm, Non Residential |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
With an allowance recorded: | 6,482 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember |  | 6,654 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 6,482 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember |  | 6,654 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
Fair value | 5,597 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember |  | 5,901 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
Allowance For Loan Losses Allocated |  |  |
With no related allowance recorded: | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember |  | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
With an allowance recorded: | 885 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember |  | 753 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
Average Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember | 104 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember | 58 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
With an allowance recorded: | 6,568 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember | 6,740 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember | 6,698 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
Cash Basis Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_NonFarmNonResidentialReceivablesMember
Agriculture |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember
Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember
Fair value | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember |  |
Allowance For Loan Losses Allocated |  |  |
With no related allowance recorded: | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember |  | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember
With an allowance recorded: | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember |  | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember
Average Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember
Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember
Cash Basis Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_AgricultureReceivablesMember
All Other Commercial |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded: | 256 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember |  | 292 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
With an allowance recorded: | 580 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember |  | 827 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
Recorded Investment |  |  |
With no related allowance recorded: | 256 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember |  | 292 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 580 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember |  | 827 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
Fair value | 483 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember |  | 725 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
Allowance For Loan Losses Allocated |  |  |
With no related allowance recorded: | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember |  | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
With an allowance recorded: | 97 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember |  | 102 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
Average Recorded Investment |  |  |
With no related allowance recorded: | 274 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember | 58 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
With an allowance recorded: | 704 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember | 1,046 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember | 1,112 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
Cash Basis Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherCommercialReceivablesMember
First Liens |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
With an allowance recorded: | 265 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember |  | 33 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 265 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember |  | 33 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
Fair value | 265 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember |  | 33 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
Allowance For Loan Losses Allocated |  |  |
With no related allowance recorded: | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember |  | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
With an allowance recorded: | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember |  | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
Average Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember | 5 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
With an allowance recorded: | 149 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember | 37 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember | 35 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
Cash Basis Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_FirstMortgageMember
Home Equity |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
Fair value | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember |  | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
Allowance For Loan Losses Allocated |  |  |
With no related allowance recorded: | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember |  | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
With an allowance recorded: | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember |  | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
Average Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
Cash Basis Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_HomeEquityMember
Junior Liens |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
Fair value | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember |  | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
Allowance For Loan Losses Allocated |  |  |
With no related allowance recorded: | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember |  | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
With an allowance recorded: | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember |  | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
Average Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
Cash Basis Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_SecondMortgageMember
Multifamily |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
Fair value | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember |  | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
Allowance For Loan Losses Allocated |  |  |
With no related allowance recorded: | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember |  | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
With an allowance recorded: | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember |  | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
Average Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
Cash Basis Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_MultifamilyMember
All Other Residential |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
Fair value | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
Allowance For Loan Losses Allocated |  |  |
With no related allowance recorded: | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember |  | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
With an allowance recorded: | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember |  | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
Average Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
Cash Basis Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherResidentialReceivablesMember
Motor Vehicle |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
Fair value | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember |  | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
Allowance For Loan Losses Allocated |  |  |
With no related allowance recorded: | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember |  | 0 thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
With an allowance recorded: | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember |  | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
Average Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
Cash Basis Interest Income Recognized |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_AutomobileLoanMember
All Other Consumer |  |  |
Unpaid Principal Balance |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember
With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember
Recorded Investment |  |  |
With no related allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember
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Fair value | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember |  | 0 us-gaap_ImpairedFinancingReceivableRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember
Allowance For Loan Losses Allocated |  |  |
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With an allowance recorded: | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember |  | 0 thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember
Average Recorded Investment |  |  |
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With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember
Interest Income Recognized |  |  |
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With an allowance recorded: | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember | 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember
Cash Basis Interest Income Recognized |  |  |
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With an allowance recorded: | $ 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember | $ 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember | $ 0 us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = thff_OtherConsumerReceivablesMember

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