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Number of major customers.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of loss from the write-down 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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Introduction and Basis of Presentation - Additional Information (Detail)		12 Months Ended
	Jul. 01, 2021 USD ($)	Dec. 31, 2021 USD ($) Customer	Dec. 31, 2020 USD ($) Customer	Dec. 31, 2019 USD ($) Customer
Introduction And Basis Of Presentation [Line Items]
Equity method investment \| $		$ 218,763,000	$ 190,898,000
Impairment of goodwill \| $	$ 0	$ 0	$ 0	$ 0
Sales Revenue, Services, Net \| Customer Concentration Risk
Introduction And Basis Of Presentation [Line Items]
Number of major customers accounted for 10.0% or more of revenues		1	1	1
Sales Revenue, Services, Net \| Customer Concentration Risk \| Blackrock Inc [Member]
Introduction And Basis Of Presentation [Line Items]
Percentage of operating revenues accounted for by major customer		12.70%	11.00%	11.50%
Sales Revenue, Services, Net \| Index [Member] \| Customer Concentration Risk \| Blackrock Inc [Member]
Introduction And Basis Of Presentation [Line Items]
Percentage of operating revenues accounted for by major customer		20.40%	18.00%	18.90%
Sales Revenue, Services, Net \| Analytics [Member] \| Customer Concentration Risk
Introduction And Basis Of Presentation [Line Items]
Number of major customers accounted for 10.0% or more of revenues		0	0	0
Sales Revenue, Services, Net \| ESG and Climate [Member] \| Customer Concentration Risk
Introduction And Basis Of Presentation [Line Items]
Number of major customers accounted for 10.0% or more of revenues		0	0	0
Sales Revenue, Services, Net \| All Other [Member] \| Customer Concentration Risk
Introduction And Basis Of Presentation [Line Items]
Number of major customers accounted for 10.0% or more of revenues		0	0	0
Minimum [Member] \| Software and Software Development Costs [Member]
Introduction And Basis Of Presentation [Line Items]
Estimates of useful lives		3 years
Maximum [Member] \| Software and Software Development Costs [Member]
Introduction And Basis Of Presentation [Line Items]
Estimates of useful lives		5 years
The Burgiss Group, LLC [Member]
Introduction And Basis Of Presentation [Line Items]
Equity method investment \| $		$ 218,800,000
Equity method investment, ownership percentage		33.60%