XML 36 R105.htm IDEA: XBRL DOCUMENT v3.20.1

Fair Value (Quantitative information about impaired loans) (Details) - Discounted appraisal value [Member] - Level 3 [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
Discounted appraisal value at fair value	$ 19,135	$ 20,045
Loans Receivable, Collateralized By Livestock [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount	30.00%	30.00%
Loans Receivable, Collateralized By Accounts Receivable [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount		50.00%
Loans Receivable, Collateralized By Accounts Receivable [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount	25.00%
Loans Receivable, Collateralized By Accounts Receivable [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount	50.00%
Real Estate [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount	20.00%	20.00%
Real Estate [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount	30.00%	30.00%
Equipment [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount	20.00%	20.00%
Equipment [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount	40.00%	40.00%
Cash crop inventory [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount	40.00%
Cash crop inventory [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount		30.00%
Cash crop inventory [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount		40.00%
Other inventory [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount	50.00%
Other inventory [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount		45.00%
Other inventory [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount		50.00%
Liquor License [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount		75.00%
Furniture and Fixtures [Member] | Minimum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount		35.00%
Furniture and Fixtures [Member] | Maximum [Member]
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31)
ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount		45.00%

X

- Definition

Impaired Financing Receivable, Fair Value Disclosure

+ References

No definition available.

+ Details

Name:	isba_ImpairedFinancingReceivableFairValueDisclosure
Namespace Prefix:	isba_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Impaired Financing Receivable, Fair Value Disclosure, Appraised Value Discount

+ References

No definition available.

+ Details

Name:	isba_ImpairedFinancingReceivableFairValueDisclosureAppraisedValueDiscount
Namespace Prefix:	isba_
Data Type:	num:percentItemType
Balance Type:	na
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_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_ValuationTechniqueAxis=isba_DiscountedAppraisalValueValuationTechniqueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=isba_LoansReceivableCollateralizedByLivestockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=isba_LoansReceivableCollateralizedByAccountsReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=isba_LoansReceivableCollateralizedByRealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=isba_LoansReceivableCollateralizedByEquipmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=isba_LoansReceivableCollateralizedByCashCropInventoryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=isba_LoansReceivableCollateralizedByOtherInventoryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=isba_LoansReceivableCollateralizedByLiquorLicenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FairValueByAssetClassAxis=us-gaap_FurnitureAndFixturesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: