Stock repurchase program termination period.

No definition available.

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Namespace Prefix:	ttgt_
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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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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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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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-Name Accounting Standards Codification
-Topic 505
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-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
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- Details

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- Details

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Stockholders' Equity - Additional Information (Detail) - USD ($)		3 Months Ended				6 Months Ended
	May 01, 2020	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Nov. 30, 2018
Schedule of Trading Securities and Other Trading Assets [Line Items]
Common stock repurchase, amount			$ 14,824,000	$ 3,762,000	$ 3,125,000
2007 and 2017 Plans [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Common stock reserved		2,376,015				2,376,015
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						2020-05
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
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