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Leases - Additional Information (Detail) $ in Millions | 3 Months Ended
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Mar. 31, 2021 USD ($)
Topic 842 [Member] | SiriusDecisions, Inc [Member] | Facility Lease [Member] |
Lessee Lease Description [Line Items] |
Right-of-use asset impairments | $ 1.4

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- 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

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- Definition Amount of loss from impairment of right-of-use asset from operating lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 25 -Paragraph 6 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121593497&loc=SL77918431-209957 + Details
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- Details
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- Details
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- Details
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