v3.22.1

Revenue Recognition - Disaggregation of Operating Revenue (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Disaggregation Of Revenue [Line Items]
Operating revenues	$ 559,945	$ 478,423
Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	330,759	292,491
Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	139,797	134,017
ESG and Climate [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	52,029	34,750
All Other - Private Assets [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	37,360	17,165
Recurring Subscriptions [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	399,760	337,732
Recurring Subscriptions [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	174,498	155,117
Recurring Subscriptions [Member] | Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	137,799	131,672
Recurring Subscriptions [Member] | ESG and Climate [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	50,572	34,140
Recurring Subscriptions [Member] | All Other - Private Assets [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	36,891	16,803
Asset-based Fees [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	145,053	126,706
Asset-based Fees [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	145,053	126,706
Non-recurring [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	15,132	13,985
Non-recurring [Member] | Index [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	11,208	10,668
Non-recurring [Member] | Analytics [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	1,998	2,345
Non-recurring [Member] | ESG and Climate [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	1,457	610
Non-recurring [Member] | All Other - Private Assets [Member]
Disaggregation Of Revenue [Line Items]
Operating revenues	$ 469	$ 362

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