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Goodwill and Intangible Assets - Additional Information (Detail) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Finite-Lived Intangible Assets [Line Items]
Goodwill gross carrying amount				$ 1,200,000
Goodwill accumulated impairment losses				205,900
Impairment charge	$ 139,645	$ 139,645	$ 139,645	66,235	$ 139,645	$ 0
Goodwill				973,398	475,814	565,493
Amortization expense for intangible assets				48,600	42,200	21,500
InformaTechTarget [Member]
Finite-Lived Intangible Assets [Line Items]
Impairment charge	$ 139,600			66,200
InformaTechTarget [Member] \| Industry Dive [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill				186,100
InformaTechTarget [Member] \| Internal Use Software [Member]
Finite-Lived Intangible Assets [Line Items]
Capitalized internal-use software				$ 6,500	$ 6,700	$ 2,800
Level 3 [Member] \| Discount Rate [Member] \| Industry Dive [Member]
Finite-Lived Intangible Assets [Line Items]
Rate used in impairment test				10.5	12.1
Level 3 [Member] \| Long-Term Revenue Growth Rate [Member] \| Industry Dive [Member]
Finite-Lived Intangible Assets [Line Items]
Rate used in impairment test				3	2.1