Consolidated Statements of Financial Condition (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
ASSETS
Cash and cash equivalents	$ 376,679	$ 451,280
Cash segregated under federal regulations	45,629	45,122
Investments, at fair value	135,831	134,861
Accounts receivable, net of allowance of $638 and $577 as of March 31, 2024 and December 31, 2023, respectively	99,878	89,839
Receivables from broker-dealers, clearing organizations and customers	662,888	687,936
Goodwill	236,706	236,706
Intangible assets, net of accumulated amortization	113,576	119,108
Furniture, equipment, leasehold improvements and capitalized software, net of accumulated depreciation and amortization	107,239	102,671
Operating lease right-of-use assets	62,006	63,045
Prepaid expenses and other assets	86,531	84,499
Total assets	1,926,963	2,015,067
Liabilities
Accrued employee compensation	28,665	60,124
Payables to broker-dealers, clearing organizations and customers	465,703	537,398
Income and other tax liabilities	2,931	7,892
Accounts payable, accrued expenses and other liabilities	33,361	37,013
Operating lease liabilities	78,070	79,677
Total liabilities	608,730	722,104
Commitments and Contingencies (Note 13)
Stockholders' equity
Preferred stock	0	0
Common stock	123	123
Additional paid-in capital	327,519	333,292
Treasury stock - Common stock voting, at cost, 3,084,169 shares and 3,041,081 shares as of March 31, 2024 and December 31, 2023 respectively	(269,005)	(260,298)
Retained earnings	1,288,247	1,244,216
Accumulated other comprehensive loss	(28,651)	(24,370)
Total stockholders' equity	1,318,233	1,292,963
Total liabilities and stockholders' equity	1,926,963	2,015,067
Series A Preferred Stock [Member]
Stockholders' equity
Preferred stock	$ 0	$ 0