Adjustments made to the holdback payment after the acquisition date.

No definition available.

Name:	iiin_BusinessCombinationHoldbackAdjustment
Namespace Prefix:	iiin_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of holdback liability for business combination, classified as current.

+ References

No definition available.

+ Details

Name:	iiin_BusinessCombinationHoldbackLiabilityCurrent
Namespace Prefix:	iiin_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 350
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482665/350-30-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 985
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481283/985-20-50-2

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479405/805-10-25-23

+ Details

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 30
-Paragraph 8
-SubTopic 30
-Topic 805
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479637/805-30-30-8

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 805
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-Section 30
-Paragraph 7
-SubTopic 30
-Topic 805
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479637/805-30-30-7

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479328/805-10-50-2

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 10
-SubTopic 20
-Topic 205
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483475/205-20-45-10

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 20
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
-Section 45
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483475/205-20-45-11

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of expected cost remaining for the specified restructuring cost.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(20))
-Publisher FASB
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
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-Subparagraph (SAB Topic 5.P.4.b.2)
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482017/420-10-50-1

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Period Type:	instant

- Details

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- Details

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- Details

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Note 3 - Business Combination (Details Textual) - USD ($)			2 Months Ended	3 Months Ended
	Nov. 26, 2024	Oct. 21, 2024	Dec. 28, 2024	Dec. 28, 2024	Dec. 30, 2023	Sep. 28, 2024
Business Combination, Holdback Liability, Current			$ 657,000	$ 657,000		$ 0
Business Combination, Acquisition Related Costs				271,000	$ 0
Disposal Group, Held-for-Sale, Not Discontinued Operations [Member]
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment			1,000,000	1,000,000
Warren Facility [Member] \| Discontinued Operations, Held-for-Sale [Member]
Disposal Group, Including Discontinued Operation, Consideration			6,100,000	6,100,000
Engineered Wire Products, Inc. [Member]
Business Combination, Consideration Transferred		$ 67,030,000
Business Combination, Holdback Liability, Current		$ 1,500,000	700,000	700,000
Business Combination, Holdback Adjustment			(800,000)
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual				7,600,000
Restructuring Reserve, Current			129,000	129,000
Restructuring and Related Cost, Expected Cost Remaining			1,200,000	1,200,000
Business Combination, Acquisition Related Costs				226,000
Engineered Wire Products, Inc. [Member] \| Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life		20 years
Engineered Wire Products, Inc. [Member] \| Noncompete Agreements [Member]
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life		4 years
Engineered Wire Products, Inc. [Member] \| Trade Names [Member]
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life		1 year
Engineered Wire Products, Inc. [Member] \| Patents [Member]
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life		7 years
O'Brien Wire Products of Texas [Member]
Business Combination, Consideration Transferred	$ 5,116,000
Restructuring Reserve, Current			11,000	11,000
Restructuring and Related Cost, Expected Cost Remaining			$ 600,000	600,000
Business Combination, Acquisition Related Costs				$ 45,000
O'Brien Wire Products of Texas [Member] \| Customer Relationships [Member]
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life	20 years
O'Brien Wire Products of Texas [Member] \| Noncompete Agreements [Member]
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life	5 years