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Goodwill - Additional Information (Detail) $ in Thousands	3 Months Ended
Goodwill - Additional Information (Detail) $ in Thousands	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2024 USD ($)
Finite-Lived Intangible Assets [Line Items]
Goodwill gross carrying amount	$ 1,200,000
Goodwill accumulated impairment losses	665,000
Impairment charge	459,100	$ 0
Goodwill	515,510		$ 973,398
Industry Dive [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment charge	127,400
Goodwill	141,700		269,100
Industry Dive [Member] \| As Reported [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill			$ 186,100
Canalys [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment charge	19,700
Goodwill	30,800
Bluefin Legacy [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment charge	123,500
Goodwill	53,300
legacy TechTarget [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment charge	188,500
Goodwill	$ 248,200
Level 3 [Member] \| Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Rate used in impairment test	0.10
Level 3 [Member] \| Discount Rate [Member] \| Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Rate used in impairment test	0.12
Level 3 [Member] \| Long-Term Revenue Growth Rate [Member]
Finite-Lived Intangible Assets [Line Items]
Rate used in impairment test	0.03