Stock repurchase program termination period.

No definition available.

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Namespace Prefix:	ttgt_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- 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

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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

- Definition

Period which shares may be purchased under a stock repurchase plan authorized by an entity's Board of Directors, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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

- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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Balance Type:	debit
Period Type:	duration

- Details

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- Details

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Stockholders' Equity - Additional Information (Detail) - USD ($)		3 Months Ended			9 Months Ended
	May 01, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2020	Nov. 30, 2018
2007 and 2017 Plans [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Common stock reserved		1,803,002			1,803,002
November 2018 Repurchase Program [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Common stock repurchased, shares				736,760
Common stock repurchase, amount			$ 0	$ 14,800,000
Common stock repurchase termination period					May 01, 2020
November 2018 Repurchase Program [Member] \| Maximum [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Common stock repurchase authorized amount						$ 25,000,000.0
May 2020 Repurchase Program [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Common stock repurchase, amount		$ 0	$ 0
Common stock repurchase program, term	2 years
May 2020 Repurchase Program [Member] \| Maximum [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Common stock repurchase authorized amount	$ 25,000,000.0