XML 60 R50.htm IDEA: XBRL DOCUMENT
v3.26.1

Loans - Collateral Dependent Loans (Details) - USD ($) $ in Thousands | Jun. 30, 2026 | Dec. 31, 2025
--- | --- | ---
Total |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | $ 22,054 | $ 21,194
Allowance on collateral dependent loans, individually evaluated | 332 | 411
Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 9,807 | 8,386
Residential Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 5,535 | 4,893
Other (Includes Equipment, Machinery and Other Assets) |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 6,712 | 7,915
Owner-occupied commercial real estate | Total |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated |  | 1,654
Allowance on collateral dependent loans, individually evaluated |  | 0
Owner-occupied commercial real estate | Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated |  | 1,654
Owner-occupied commercial real estate | Residential Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated |  | 0
Owner-occupied commercial real estate | Other (Includes Equipment, Machinery and Other Assets) |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated |  | 0
Small business lending | Loans Insured or Guaranteed by US Government Authorities |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 19,200 | 13,600
Small business lending | Total |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 16,344 | 14,413
Allowance on collateral dependent loans, individually evaluated | 332 | 411
Small business lending | Total | Loans Insured or Guaranteed by US Government Authorities |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 11,800 | 8,500
Small business lending | Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 9,807 | 6,732
Small business lending | Residential Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 0 | 0
Small business lending | Other (Includes Equipment, Machinery and Other Assets) |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 6,537 | 7,681
Residential mortgage | Total |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 5,501 | 4,893
Allowance on collateral dependent loans, individually evaluated | 0 | 0
Residential mortgage | Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 0 | 0
Residential mortgage | Residential Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 5,501 | 4,893
Residential mortgage | Other (Includes Equipment, Machinery and Other Assets) |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 0 | 0
Other consumer loans | Total |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 209 | 234
Allowance on collateral dependent loans, individually evaluated | 0 | 0
Other consumer loans | Commercial Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 0 | 0
Other consumer loans | Residential Real Estate |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | 34 | 0
Other consumer loans | Other (Includes Equipment, Machinery and Other Assets) |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Amortized cost basis of collateral dependent loans, individually evaluated | $ 175 | $ 234

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 310 -SubTopic 20 -Name Accounting Standards Codification -Section 40 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481628/310-20-40-7 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481990/310-10-45-2 + Details
Name: | us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of allowance for credit loss on financing receivable evaluated on individual basis. Excludes financing receivable evaluated on collective basis. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.5.a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480418/310-10-S99-4 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11B -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 30 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479391/326-20-30-2 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of financing receivable individually evaluated for credit loss. Excludes financing receivable collectively evaluated for credit loss. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.5.a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480418/310-10-S99-4 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11C -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-11C + Details
Name: | us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_CollateralAxis=us-gaap_CollateralPledgedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=inbk_CommercialRealEstate1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=inbk_ResidentialRealEstate1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=inbk_OtherRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

X
- Details
Name: | us-gaap_LoansInsuredOrGuaranteedByGovernmentAuthoritiesAxis=us-gaap_LoansInsuredOrGuaranteedByUsGovernmentAuthoritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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