Represents the non-cash decrease in operating lease liabilities and right-of-use assets.

No definition available.

Name:	intt_DecreaseInOperatingLeaseLiabilitiesAndRightOfUseAssetsNonCash
Namespace Prefix:	intt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the non-cash increase in operating lease liabilities and right-of-use assets.

+ References

No definition available.

+ Details

Name:	intt_IncreaseInOperatingLeaseLiabilitiesAndRightofuseAssetsNonCash
Namespace Prefix:	intt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the amount of increase in the area of an operating lease during the period.

+ References

No definition available.

+ Details

Name:	intt_OperatingLeaseIncreaseInArea
Namespace Prefix:	intt_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	duration

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980

+ Details

Name:	us-gaap_LesseeOperatingLeaseRenewalTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_LesseeOperatingLeaseTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of amortization expense for right-of-use asset from operating lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

+ Details

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

- Details

Name:	srt_StatementGeographicalAxis=intt_MansfieldMassachusettsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

Note 7 - Leases (Details Textual) $ in Thousands		3 Months Ended		6 Months Ended
Note 7 - Leases (Details Textual) $ in Thousands	Apr. 08, 2019 USD ($) ft²	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jan. 23, 2020	Mar. 31, 2019
Operating Lease, Right-of-Use Asset, Amortization Expense		$ 328	$ 295	$ 653	$ 601
Mansfield, Massachusetts [Member]
Lessee, Operating Lease, Renewal Term (Month)	3 years 120 days
Increase in Operating Lease Liabilities and Right-of-Use Assets, Non-cash	$ 1,819
Operating Lease, Increase in Area (Square Foot) \| ft²	6,100
Lease Agreement, EMS Facility in Fremont, California [Member]
Lessee, Operating Lease, Renewal Term (Month)						5 years 30 days
Increase in Operating Lease Liabilities and Right-of-Use Assets, Non-cash				$ 1,176
Lease Agreement, Ambrell’s U.K [Member]
Lessee, Operating Lease, Term of Contract (Year)							15 years
Decrease In Operating Lease Liabilities and Right-of-Use Assets, Non-cash					$ 486