Goodwill and Other Intangible Assets - Summary of Goodwill by Segment and Changes in Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 85,165	$ 76,169
Acquisitions	158,569	10,178
Translation adjustments	161	(1,182)
Goodwill, Ending Balance	243,895	85,165
Product Segment [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	12,518	2,438
Reassignment	(12,518)
Acquisitions		10,178
Translation adjustments		(98)
Goodwill, Ending Balance		12,518
Research Segment [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	72,647	73,731
Reassignment	12,518
Acquisitions	16,025
Translation adjustments	121	(1,084)
Goodwill, Ending Balance	101,311	$ 72,647
Sirius Decisions Segment [Member]
Goodwill [Line Items]
Acquisitions	142,544
Translation adjustments	40
Goodwill, Ending Balance	$ 142,584

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of transfers into (out of) an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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