Significant Accounting Policies - Additional Information (Detail) shares in Millions	3 Months Ended
Mar. 31, 2025 USD ($) Segment shares	Mar. 31, 2024 USD ($) shares
Significant Accounting Policies [Line Items]
Deferred revenue payment terms	30 days
Number of reporting segment	1
Number of operating segment	1
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]	srt:ChiefExecutiveOfficerMember
Impairment charge \| $	$ 459,100,000	$ 0
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares	1.2
Industry Dive [Member]
Significant Accounting Policies [Line Items]
Impairment charge \| $	$ 127,400,000
Informa TechTarget [Member]
Significant Accounting Policies [Line Items]
Number of reporting segment	1
Number of operating segment	1
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]	srt:ChiefExecutiveOfficerMember
Impairment of long-lived assets \| $	$ 0
Restricted Stock Units (RSUs) [Member]
Significant Accounting Policies [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares	1.4	0.0
Convertible Notes [Member]
Significant Accounting Policies [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares		0.0

Deferred revenue payment terms.

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- Definition

Significant accounting policies.

+ References

No definition available.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
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- Definition

Amount of impairment loss from asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

+ References

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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- Definition

Indicates title and position of individual or name of group identified as chief operating decision maker (CODM) for segment reporting.

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