Significant Accounting Policies - Summary of Information Services Revenue by Timing of Recognition (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Significant Accounting Policies [Line Items]
Revenues	$ 184,795	$ 125,490	$ 353,773	$ 249,981
Information Services [Member]
Significant Accounting Policies [Line Items]
Revenues	8,427	7,156	17,069	14,522
Information Services [Member] | Transferred over Time [Member]
Significant Accounting Policies [Line Items]
Revenues	7,819	7,050	15,625	14,269
Information Services [Member] | Transferred at a Point in Time [Member]
Significant Accounting Policies [Line Items]
Revenues	$ 608	$ 106	$ 1,444	$ 253