Employee Benefits - Benefit Payments Expected to be Paid for Agreements (Detail) $ in Thousands	Jun. 30, 2024 USD ($)
Defined Benefit Plan Disclosure [Line Items]
2025	$ 147
2026	179
2027	190
2028	203
2029	201
Thereafter	905
Deferred Compensation Agreements [Member]
Defined Benefit Plan Disclosure [Line Items]
2025	90
2026	228
2027	241
2028	263
2029	294
Thereafter	3,905
Total	$ 5,021

Defined benefit plan expected future benefit payments.

No definition available.

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Namespace Prefix:	iroq_
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- 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

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Period Type:	duration

- Definition

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

+ Details

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- Definition

Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

+ References

+ Details

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- Definition

Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

+ References

+ Details

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- Definition

Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

+ References

+ Details

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- Definition

Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

+ References

+ Details

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- Definition

Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

+ References

+ Details

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- Details

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