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

The amount of increase (decrease) in operating lease liabilities.

+ References

No definition available.

+ Details

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

- Definition

The amount of increase (decrease) in operating lease right of use assets.

+ References

No definition available.

+ Details

Name:	intt_IncreaseDecreaseInOperatingLeaseRightOfUseAsset
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

The remaining lease term of operating leases.

+ References

No definition available.

+ Details

Name:	intt_OperatingLeaseRemainingLeaseTerm
Namespace Prefix:	intt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- 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

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=77888426&loc=SL77918673-209980

+ Details

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

- Details

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

- Details

Name:	us-gaap_ProspectiveAdoptionOfNewAccountingPronouncementsAxis=us-gaap_PreviousAccountingGuidanceMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201602Member
Namespace Prefix:
Data Type:	na
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Note 7 - Leases (Details Textual) $ in Thousands			1 Months Ended	6 Months Ended
Note 7 - Leases (Details Textual) $ in Thousands	Apr. 08, 2019 USD ($) ft²	Jan. 01, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)
Increase (Decrease) in Operating Lease Liabilities				$ (668)
UNITED KINGDOM
Decrease In Operating Lease Liabilities and Right-of-Use Assets, Non-cash			$ 486	$ 486
UNITED KINGDOM \| Previous Accounting Guidance [Member]
Lessee, Operating Lease, Term of Contract				15 years
Mansfield, Massachusetts [Member]
Operating Lease, Remaining Lease Term	3 years 120 days
Operating Lease, Increase in Area \| ft²	6,100
Increase in Operating Lease Liabilities and Right-of-Use Assets, Non-cash	$ 1,819			$ 1,819
Accounting Standards Update 2016-02 [Member]
Increase (Decrease) in Operating Lease Liabilities		$ 5,197
Increase (Decrease) in Operating Lease Right-of-Use Assets		$ 4,816