XML 47 R38.htm IDEA: XBRL DOCUMENT
v3.23.1

Basis of Presentation (Details) - USD ($) |  | 3 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jan. 01, 2023 | Mar. 31, 2023 | Dec. 31, 2022 | Mar. 31, 2022 | Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | $ 12,640,000 | $ 9,850,000 | $ 9,204,000 | $ 9,103,000
Credit Loss, Financial Instrument |  | ACL - Loans: The ACL on loans is calculated in accordance with ASC 326 and is deducted from the amortized cost basis of loans to present our best estimate of the net amount expected to be collected. The ACL is established through a provision for credit losses charged to earnings. Loan losses are charged against the allowance when we believe the uncollectability of the loan balance is confirmed. Subsequent recoveries, if any, are credited to the allowance. We made an accounting policy election to exclude accrued interest receivable on loans from the estimate of credit losses. We evaluate the ACL on a regular basis. Our periodic review of the collectability of loans considers historical experience, the nature and volume of the loan portfolio, adverse situations that may affect the borrower’s ability to repay, estimated value of any underlying collateral, prevailing economic conditions, and reasonable and supportable forecasts. This evaluation is inherently subjective as it requires estimates that are susceptible to significant revision as more information becomes available. The ACL consists of a general component and loans individually analyzed. The general component covers loans not specifically analyzed and is based on historical loss experience, current conditions, and reasonable and supportable forecasts. The general component also includes uncertainties that we believe could affect our estimate of probable losses based on qualitative factors. Loans in nonaccrual status are individually analyzed on a loan-by-loan basis. Loans evaluated individually are not included in the general, or pooled, component of the ACL. For collateralized loans, the loan's specific allowance is measured by the fair value of the collateral approach. The specific reserve is based on the fair value of the collateral, less costs to sell if foreclosure is probable, and an allowance is established when the collateral value is lower than the carrying value of the loan. When the discounted cash flow method is used to measure the loan's specific allowance, the effective interest rate is used to discount expected cash flows to incorporate expected prepayments. An allowance is established when the discounted cash flows are lower than the carrying value of the loan. Large groups of smaller-balance, homogeneous loans are collectively evaluated for measurement of an allowance. Off Balance Sheet Credit Related Financial Instruments: In the ordinary course of business, we have entered into commitments to extend credit, including commitments under credit card arrangements, commercial lines of credit, home equity lines of credit, commercial letters of credit, and standby letters of credit. Such financial instruments are recorded only when funded. In connection with these commitments, we established an allowance for credit losses related to off-balance-sheet credit exposures. The allowance, recorded in a liability account, is calculated in accordance with ASC 326 and represents expected credit losses over the contractual period for which we are exposed to credit risk resulting from a contractual obligation to extend credit. The estimate of expected credit losses considers both the likelihood that funding will occur and the amount expected to be funded over the estimated remaining life of the commitment. The likelihood and expected amount of funding are based on historical utilization rates. No allowance is recognized if we have the unconditional right to cancel the obligation. The allowance is reported as a component of accrued interest payable and other liabilities in our consolidated balance sheets. Adjustments to the allowance are reported in our income statement as a component of provision for credit losses. |  |  |
Commercial Real Estate |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | $ 6,036,000 | 461,000 |  |
Commercial [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | 817,000 | 860,000 | 1,245,000 | 1,740,000
Agricultural [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | 265,000 | 577,000 | 383,000 | 289,000
Unallocated Financing Receivables [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss |  | 0 | $ 6,374,000 | $ 6,143,000 | $ 5,419,000
Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | $ 12,594,000 |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Commitments to Extend Credit |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Off-Balance-Sheet, Credit Loss, Liability | 315,000 |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Commercial Real Estate |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 5,993,000 |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Commercial [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 802,000 |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Agricultural [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 330,000 |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Residential Mortgage |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 4,152,000 |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Consumer Loan |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 1,317,000 |  |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | Unallocated Financing Receivables [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 0 |  |  |  |
Accounting Standards Update 2016-13 |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 2,744,000 | 2,744,000 |  |  |
Accounting Standards Update 2016-13 | Commitments to Extend Credit |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Off-Balance-Sheet, Credit Loss, Liability | 315,000 |  |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (249,000) |  |  |  |
Accounting Standards Update 2016-13 | Loans Receivable |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (2,168,000) |  |  |  |
Accounting Standards Update 2016-13 | Commercial Real Estate |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 5,532,000 | 5,532,000 |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (4,370,000) |  |  |  |
Accounting Standards Update 2016-13 | Commercial [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | (58,000) | (58,000) |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | 46,000 |  |  |  |
Accounting Standards Update 2016-13 | Agricultural [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | (247,000) | (247,000) |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | 195,000 |  |  |  |
Accounting Standards Update 2016-13 | Residential Mortgage |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 3,535,000 |  |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (2,793,000) |  |  |  |
Accounting Standards Update 2016-13 | Consumer Loan |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 356,000 |  |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | (281,000) |  |  |  |
Accounting Standards Update 2016-13 | Unallocated Financing Receivables [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | (6,374,000) | $ (6,374,000) |  |  |
Financing Receivable, Allowance for Credit Losses, Effect of Change in Method | 5,035,000 |  |  |  |
Pre Adoption Allowance |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 9,850,000 |  |  |  |
Pre Adoption Allowance | Commitments to Extend Credit |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Off-Balance-Sheet, Credit Loss, Liability | 0 |  |  |  |
Pre Adoption Allowance | Commercial Real Estate |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 461,000 |  |  |  |
Pre Adoption Allowance | Commercial [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 860,000 |  |  |  |
Pre Adoption Allowance | Agricultural [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 577,000 |  |  |  |
Pre Adoption Allowance | Residential Mortgage |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 617,000 |  |  |  |
Pre Adoption Allowance | Consumer Loan |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | 961,000 |  |  |  |
Pre Adoption Allowance | Unallocated Financing Receivables [Member] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Financing Receivable, Allowance for Credit Loss | $ 6,374,000 |  |  |  |

X
- Definition Disclosure of accounting policy for credit loss on financial instrument measured at amortized cost basis, net investment in lease, off-balance sheet credit exposure, and available-for-sale debt security. Includes, but is not limited to, methodology used to estimate allowance for credit loss, how writeoff of uncollectible amount is recognized, and determination of past due status and nonaccrual status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 35 -Paragraph 7A -URI https://asc.fasb.org/extlink&oid=125515542&loc=SL120269220-210453 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 3D -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL120267969-210447 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 7 -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922895-210455 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 35 -Paragraph 13A -URI https://asc.fasb.org/extlink&oid=125515542&loc=SL120267917-210453 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 35 -Paragraph 8A -URI https://asc.fasb.org/extlink&oid=124266218&loc=SL120267834-210445 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 30 -Paragraph 4A -URI https://asc.fasb.org/extlink&oid=124256539&loc=SL120269210-210444 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919260-210447 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=124255206&loc=SL120267845-210446 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 14 -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 21 -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919272-210447 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 30 -Paragraph 5A -URI https://asc.fasb.org/extlink&oid=124256539&loc=SL120254536-210444 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 3C -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL120267966-210447 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 30 -Paragraph 1B -URI https://asc.fasb.org/extlink&oid=124268681&loc=SL120267897-210452 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 11 -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919244-210447 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 3D -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL120267862-210455 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.M.Q4) -URI https://asc.fasb.org/extlink&oid=122651532&loc=SL122037091-237805 Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 3C -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL120267859-210455 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 3A -URI https://asc.fasb.org/extlink&oid=124269663&loc=SL120267853-210455 + Details
Name: | us-gaap_CreditLossFinancialInstrumentPolicyTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)(2)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(4)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (3) Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (c) Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (1) + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The effect of a change in method or methods for calculating the allowance for credit losses on the current period provision. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (d) -URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLossesEffectOfChangeInMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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

X
- Definition Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=121611286&loc=d3e11927-110247 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82919202-210446 + Details
Name: | us-gaap_OffBalanceSheetCreditLossLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

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

X
- Details
Name: | srt_CumulativeEffectPeriodOfAdoptionAxis=srt_CumulativeEffectPeriodOfAdoptionAdjustedBalanceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_CommitmentsToExtendCreditMember
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_ConsumerLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CumulativeEffectPeriodOfAdoptionAxis=us-gaap_AccountingStandardsUpdate201613Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_LoansReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CumulativeEffectPeriodOfAdoptionAxis=isba_PreAdoptionAllowanceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |