Lessee, Operating Lease, Square Footage Leased

No definition available.

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Namespace Prefix:	intt_
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Period Type:	instant

- Definition

Semi-Annual Lease Payments

+ References

No definition available.

+ Details

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Namespace Prefix:	intt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of increase (decrease) in obligation for operating lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (g)(1)
-SubTopic 20
-Topic 842
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-4

+ Details

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

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-3

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of periodic reduction over lease term of carrying amount of right-of-use asset from operating lease.

+ References

+ Details

Name:	us-gaap_OperatingLeaseRightOfUseAssetAmortizationExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LeaseContractualTermAxis=intt_WarehouseAndOfficeSpaceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

LEASES - Narrative (Details) ft² in Thousands, $ in Thousands		3 Months Ended
	Mar. 12, 2024 USD ($) ft²	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)
Lessee, Lease, Description [Table]
Amortization of ROU assets		$ 600	$ 400
Operating lease liabilities		(523)	$ (447)
Alfamation
Lessee, Lease, Description [Table]
Leased premise (in square feet) \| ft²	52
Alfamation \| Warehouse and Office Space
Lessee, Lease, Description [Table]
Semi-annual lease payments		100
Operating lease liabilities	$ 1,700	$ 0