Receivables from and Payables to Broker-dealers, Clearing organizations and Customers - Schedule of Receivables from and Payables to Broker-dealers, Clearing Organizations and Customers (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Receivables from broker-dealers, clearing organizations and customers:
Securities failed-to-deliver - broker-dealers and clearing organizations	$ 189,929	$ 152,766
Securities failed-to-deliver - customers	333,607	182,052
Deposits with clearing organizations and broker-dealers	87,962	68,565
Other	6,319	4,963
Total	617,817	408,346
Payables to broker-dealers, clearing organizations and customers:
Securities failed-to-receive - broker-dealers and clearing organizations	251,076	166,010
Securities failed-to-receive - customers	115,365	59,879
Other	8,770	3,436
Total	$ 375,211	$ 229,325