XML 37 R27.htm IDEA: XBRL DOCUMENT
v3.5.0.2

Allowance for Loan Losses (Details 2) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2016 | Jun. 30, 2015 | Jun. 30, 2016 | Jun. 30, 2015 | Dec. 31, 2015
Unpaid Principal Balance |  |  |  |  |
TOTAL | $ 9,895 |  | $ 9,895 |  | $ 10,018
Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 1,813 |  | 1,813 |  | 2,352
Fair value | 9,602 |  | 9,602 |  | 9,725
Allowance For Loan Losses Allocated |  |  |  |  |
TOTAL | 918 |  | 918 |  | 1,159
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, Average Recorded Investment | 8,875 | $ 15,440 | 9,157 | $ 15,159 | 13,157
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
TOTAL | 0 | 0 | 0 | 0 | 0
Commercial & Industrial |  |  |  |  |
Unpaid Principal Balance |  |  |  |  |
With no related allowance recorded: | 529 |  | 529 |  | 1,516
With an allowance recorded: | 994 |  | 994 |  | 998
Recorded Investment |  |  |  |  |
With no related allowance recorded: | 236 |  | 236 |  | 1,223
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 994 |  | 994 |  | 998
Fair value | 906 |  | 906 |  | 786
Allowance For Loan Losses Allocated |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 88 |  | 88 |  | 212
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment | 650 | 2,779 | 841 | 2,161 | 1,796
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 797 | 4,413 | 864 | 4,900 | 3,463
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Farmland |  |  |  |  |
Unpaid Principal Balance |  |  |  |  |
With no related allowance recorded: | 1,465 |  | 1,465 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Recorded Investment |  |  |  |  |
With no related allowance recorded: | 1,465 |  | 1,465 |  | 0
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 |  | 0 |  | 0
Fair value | 0 |  | 0 |  | 0
Allowance For Loan Losses Allocated |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment | 733 | 0 | 488 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Non Farm, Non Residential |  |  |  |  |
Unpaid Principal Balance |  |  |  |  |
With no related allowance recorded: | 3,084 |  | 3,084 |  | 3,202
With an allowance recorded: | 1,129 |  | 1,129 |  | 1,415
Recorded Investment |  |  |  |  |
With no related allowance recorded: | 3,084 |  | 3,084 |  | 3,202
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 1,129 |  | 1,129 |  | 1,415
Fair value | 431 |  | 431 |  | 674
Allowance For Loan Losses Allocated |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 698 |  | 698 |  | 741
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment | 3,119 | 1,978 | 3,147 | 1,318 | 2,080
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 1,153 | 4,417 | 1,240 | 5,162 | 3,682
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Agriculture |  |  |  |  |
Unpaid Principal Balance |  |  |  |  |
With no related allowance recorded: | 635 |  | 635 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Recorded Investment |  |  |  |  |
With no related allowance recorded: | 635 |  | 635 |  | 0
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 |  | 0 |  | 0
Fair value | 0 |  | 0 |  | 0
Allowance For Loan Losses Allocated |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment | 318 | 0 | 212 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
All Other Commercial |  |  |  |  |
Unpaid Principal Balance |  |  |  |  |
With no related allowance recorded: | 1,424 |  | 1,424 |  | 1,760
With an allowance recorded: | 0 |  | 0 |  | 225
Recorded Investment |  |  |  |  |
With no related allowance recorded: | 1,424 |  | 1,424 |  | 1,760
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 |  | 0 |  | 225
Fair value | 0 |  | 0 |  | 225
Allowance For Loan Losses Allocated |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment | 1,431 | 1,025 | 1,540 | 780 | 1,175
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 566 | 75 | 653 | 483
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
First Liens |  |  |  |  |
Unpaid Principal Balance |  |  |  |  |
With no related allowance recorded: | 27 |  | 27 |  | 29
With an allowance recorded: | 608 |  | 608 |  | 873
Recorded Investment |  |  |  |  |
With no related allowance recorded: | 27 |  | 27 |  | 29
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 608 |  | 608 |  | 873
Fair value | 476 |  | 476 |  | 667
Allowance For Loan Losses Allocated |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 132 |  | 132 |  | 206
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment | 28 | 16 | 28 | 10 | 18
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 646 | 246 | 722 | 175 | 460
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Home Equity |  |  |  |  |
Unpaid Principal Balance |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Recorded Investment |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 |  | 0 |  | 0
Fair value | 0 |  | 0 |  | 0
Allowance For Loan Losses Allocated |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Junior Liens |  |  |  |  |
Unpaid Principal Balance |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Recorded Investment |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 |  | 0 |  | 0
Fair value | 0 |  | 0 |  | 0
Allowance For Loan Losses Allocated |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Multifamily |  |  |  |  |
Unpaid Principal Balance |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Recorded Investment |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 |  | 0 |  | 0
Fair value | 0 |  | 0 |  | 0
Allowance For Loan Losses Allocated |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
All Other Residential |  |  |  |  |
Unpaid Principal Balance |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Recorded Investment |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 |  | 0 |  | 0
Fair value | 0 |  | 0 |  | 0
Allowance For Loan Losses Allocated |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Motor Vehicle |  |  |  |  |
Unpaid Principal Balance |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Recorded Investment |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 |  | 0 |  | 0
Fair value | 0 |  | 0 |  | 0
Allowance For Loan Losses Allocated |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
All Other Consumer |  |  |  |  |
Unpaid Principal Balance |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Recorded Investment |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
Impaired Financing Receivable, with Related Allowance, Recorded Investment | 0 |  | 0 |  | 0
Fair value | 0 |  | 0 |  | 0
Allowance For Loan Losses Allocated |  |  |  |  |
With no related allowance recorded: | 0 |  | 0 |  | 0
With an allowance recorded: | 0 |  | 0 |  | 0
Average Recorded Investment |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Average Recorded Investment | 0 | 0 | 0 | 0 | 0
Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Accrual Method | 0 | 0 | 0 | 0 | 0
Cash Basis Interest Income Recognized |  |  |  |  |
Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method | 0 | 0 | 0 | 0 | 0
Impaired Financing Receivable, with Related Allowance, Interest Income, Cash Basis Method | $ 0 | $ 0 | $ 0 | $ 0 | $ 0

X
- Definition -- None. No documentation exists for this element. -- + References No definition available. + Details
Name: | thff_ImpairedFinancingReceivableAllowanceForLoanLossesAbstract
Namespace Prefix: | thff_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total ofImpaired Financing Receivable loan losses alocated. + References No definition available. + Details
Name: | thff_ImpairedFinancingReceivableLoanLossesAlocated
Namespace Prefix: | thff_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of loan losses allocated in impaired financing receivables for which there is no related allowance for credit losses. + References No definition available. + Details
Name: | thff_ImpairedFinancingReceivableWithNoRelatedAllowanceForLoanLossesAllocated
Namespace Prefix: | thff_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of loan losses allocated in impaired financing receivables for which there is no related allowance for credit losses. + References No definition available. + Details
Name: | thff_ImpairedFinancingReceivableWithRelatedAllowanceForLoanLossesAllocated
Namespace Prefix: | thff_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableAverageRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_ImpairedFinancingReceivableAverageRecordedInvestmentAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_ImpairedFinancingReceivableInterestIncomeAccrualMethodAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableInterestIncomeCashBasisMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_ImpairedFinancingReceivableInterestIncomeCashBasisMethodAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_ImpairedFinancingReceivableRecordedInvestmentAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalanceAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of average investment of impaired financing receivables for which there is no related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceAverageRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of interest income, recognized on accrual basis, on financing receivables that are recognized as impaired, for which there is no related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeAccrualMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of interest income, recognized on cash basis, on financing receivables, for which there is no related allowance for credit losses and are recognized as impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeCashBasisMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of investment in impaired financing receivables for which there is no related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of average investment of impaired financing receivables for which there is a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceAverageRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of interest income, recognized on accrual basis, on financing receivables, for which there is a related allowance for credit losses and are recognized as impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeAccrualMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of interest income on financing receivables, for which there is a related allowance for credit losses, recognized on a cash-basis method of accounting that the financing receivables were impaired. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceInterestIncomeCashBasisMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of investment in impaired financing receivables for which there is a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithRelatedAllowanceUnpaidPrincipalBalance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=thff_CommercialAndIndustrialReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=thff_FarmlandMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=thff_NonFarmNonResidentialReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=thff_AgricultureReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=thff_OtherCommercialReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_FirstMortgageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_HomeEquityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_SecondMortgageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_MultifamilyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=thff_OtherResidentialReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_AutomobileLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=thff_OtherConsumerReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |