Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2023

Accounting Policies [Abstract]

Summary of Commission Revenue by Fee Type

The following table presents commission revenue by fee type:

	Year Ended December 31,
	2023		2022		2021
	(In thousands)
Commission revenue by fee type
Variable transaction fees
Disclosed trading	$	323,038	$	321,603	$	333,712
Open Trading – matched principal trading		178,517		175,440		155,465
U.S. government bonds - matched principal trading		15,222		16,978		12,400
Other		4,979		—		—
Total variable transaction fees		521,756		514,021		501,577
Distribution fees and unused minimum fees		141,208		127,162		119,431
Total commissions	$	662,964	$	641,183	$	621,008

Summary of Information Services Revenue by Timing of Recognition

The following table presents information services revenue by timing of recognition:

	Year Ended December 31,
	2023		2022		2021
	(In thousands)
Information services revenue by timing of recognition
Services transferred over time	$	45,102	$	38,452	$	37,341
Services transferred at a point in time		1,281		862		834
Total information services revenues	$	46,383	$	39,314	$	38,175

Summary of Post-Trade Services Revenue by Timing of Recognition

The following table presents post-trade services revenue by timing of recognition:

	Year Ended December 31,
	2023		2022		2021
	(In thousands)
Post-trade services revenue by timing of recognition
Services transferred over time	$	40,061	$	36,835	$	38,850
Services transferred at a point in time		117		42		72
Total post-trade services revenues	$	40,178	$	36,877	$	38,922

Summary of Revenue Recognized from Contract Liabilities and Remaining Balance

The revenue recognized from contract liabilities and the remaining balance is shown below:

	December 31, 2022			Payments received in advance of services to be performed		Revenue recognized for services performed during the period			Foreign Currency Translation		December 31, 2023
		(In thousands)
Information services	$		3,121	$	12,715	$	(12,787	)	$	—	$	3,049
Post-trade services			869		23,116		(23,107	)		45		923
Technology services			—		1,085		(518	)		—		567
Total deferred revenue	$		3,990	$	35,831	$	(35,894	)	$	45	$	4,539