Discount amount from fair value on purchase date that participants pay for shares.

No definition available.

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

- Definition

Discount rate from fair value on purchase date that participants pay for shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

+ Details

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Balance Type:	na
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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-SubTopic 10
-Topic 505
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

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Balance Type:	na
Period Type:	duration

- Definition

Aggregate change in value for stock issued during the period as a result of employee stock purchase plan.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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Note 15 - Employee Stock Purchase Plan (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Jun. 23, 2021
Stock Issued During Period, Value, Employee Stock Purchase Plan	$ 164	$ 205
Share Price (in dollars per share)	$ 8.59	$ 13.6	$ 7.3	$ 9.88	$ 13.25	$ 15.17	$ 26.26	$ 20.74
Share-based Compensation Arrangement by Share-based Payment Award, Discount Amount	$ 24	$ 31
Employee Stock Purchase Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized									250,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant	190,393
Stock Issued During Period, Shares, Employee Stock Purchase Plans (in shares)	16,674	11,780
Stock Issued During Period, Value, Employee Stock Purchase Plan	$ 140	$ 174
Shares Issued, Price Per Share (in dollars per share)	$ 7.3	$ 11.56	$ 6.2	$ 8.4	$ 11.26	$ 12.89	$ 22.32	$ 17.63
Share-Based Compensation Arrangement by Share-Based Payment Award, Discount from Market Price, Purchase Date	15.00%	15.00%
Share-based Compensation Arrangement by Share-based Payment Award, Discount Amount	$ 24	$ 31