v3.22.1

Segment Information - Operating Revenues by Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	$ 559,945	$ 478,423
Index [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	330,759	292,491
Analytics [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	139,797	134,017
ESG and Climate [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	52,029	34,750
All Other - Private Assets [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Operating revenues	$ 37,360	$ 17,165

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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