XML 79 R68.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Loans and ACL (Summary of Specific Reserves by Segments) (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Financing Receivable, Nonaccrual [Line Items] |  |
Individually Evaluated for Impairment, Loans |  | $ 22,018
Individually evaluated for impairment, ACL |  | 451
Collateral Pledged |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Individually Evaluated for Impairment, Loans | $ 1,083 | 22,018
Individually evaluated for impairment, ACL | 84 | 451
Commercial [Member] | Collateral Pledged |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Individually Evaluated for Impairment, Loans | 465 | 0
Individually evaluated for impairment, ACL | 56 | 0
Commercial Real Estate | Collateral Pledged |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Individually Evaluated for Impairment, Loans | 234 | 8,342
Individually evaluated for impairment, ACL | 28 | 12
Agricultural [Member] |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Individually Evaluated for Impairment, Loans |  | 10,935
Individually evaluated for impairment, ACL |  | 0
Agricultural [Member] | Collateral Pledged |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Individually Evaluated for Impairment, Loans | 181 | 10,935
Individually evaluated for impairment, ACL | 0 | 0
Residential Mortgage |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Individually Evaluated for Impairment, Loans |  | 2,741
Individually evaluated for impairment, ACL |  | 439
Residential Mortgage | Collateral Pledged |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Individually Evaluated for Impairment, Loans | 203 | 2,741
Individually evaluated for impairment, ACL | 0 | 439
Total consumer [Member] |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Individually Evaluated for Impairment, Loans |  | 0
Individually evaluated for impairment, ACL |  | 0
Total consumer [Member] | Collateral Pledged |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Individually Evaluated for Impairment, Loans | 0 | 0
Individually evaluated for impairment, ACL | $ 0 | $ 0

X
- Definition Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 11B -Subparagraph (g) -SubTopic 10 -Topic 310 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-11B + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-13 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph c -Publisher SEC + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The balance of financing receivables that were individually evaluated for impairment. + References Reference 1: 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 Reference 2: 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 + 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_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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