XML 60 R51.htm IDEA: XBRL DOCUMENT
v3.22.2.2

Loans and Allowance for Credit Losses - Summary of Impaired Loans (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 | Jun. 30, 2022
Financing Receivable, Impaired [Line Items] |  |
Recorded Balance | $ 1,129 | $ 1,385
Unpaid Principal Balance | 1,129 | 1,385
Specific Allowance | 0 | 0
Average Investment in Impaired Loans | 1,132 | 1,401
Interest Income Recognized | 6 | 19
Interest on Cash Basis | 5 | 17
Commercial [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Balance, Loans without a specific valuation allowance | 43 | 35
Unpaid Principal Balance, Loans without a specific valuation allowance | 43 | 35
Average Investment in Impaired Loans, Loans without a specific valuation allowance | 44 | 40
Interest Income Recognized, Loans without a specific valuation allowance | 1 | 4
Interest on Cash Basis, Loans without a specific valuation allowance | 1 | 4
Recorded Balance | 43 | 35
Unpaid Principal Balance | 43 | 35
Average Investment in Impaired Loans | 44 | 40
Interest Income Recognized | 1 | 4
Interest on Cash Basis | 1 | 4
One- to four-family [Member] |  |
Financing Receivable, Impaired [Line Items] |  |
Recorded Balance, Loans without a specific valuation allowance | 1,086 | 1,350
Unpaid Principal Balance, Loans without a specific valuation allowance | 1,086 | 1,350
Average Investment in Impaired Loans, Loans without a specific valuation allowance | 1,088 | 1,361
Interest Income Recognized, Loans without a specific valuation allowance | 5 | 15
Interest on Cash Basis, Loans without a specific valuation allowance | 4 | 13
Recorded Balance | 1,086 | 1,350
Unpaid Principal Balance | 1,086 | 1,350
Average Investment in Impaired Loans | 1,088 | 1,361
Interest Income Recognized | 5 | 15
Interest on Cash Basis | $ 4 | $ 13

X
- Definition Impaired financing receivable interest income loss accrual method. + References No definition available. + Details
Name: | iroq_ImpairedFinancingReceivableInterestIncomeLossAccrualMethod
Namespace Prefix: | iroq_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Impaired financing receivable with no related allowance interest income loss accrual method. + References No definition available. + Details
Name: | iroq_ImpairedFinancingReceivableWithNoRelatedAllowanceInterestIncomeLossAccrualMethod
Namespace Prefix: | iroq_
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_FinancingReceivableImpairedLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableAverageRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(3) -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableInterestIncomeCashBasisMethod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953550-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableRecordedInvestment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of allowance for credit losses related to recorded investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(3) -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableRelatedAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(4) -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableUnpaidPrincipalBalance
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 no related allowance for credit losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(1) -URI https://asc.fasb.org/extlink&oid=123577603&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 cash basis, on financing receivables, for which there is no related allowance for credit losses and are recognized as impaired. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(3) -URI https://asc.fasb.org/extlink&oid=123577603&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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123577603&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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(4) -URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524 + Details
Name: | us-gaap_ImpairedFinancingReceivableWithNoRelatedAllowanceUnpaidPrincipalBalance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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