Condensed Consolidated Statements of Financial Condition - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Assets
Cash and cash equivalents	$ 574,384	$ 593,646
Cash segregated under regulatory requirements	257,512	257,031
Securities owned	59,527	58,572
Marketable securities	338	349
Receivables from broker-dealers, clearing organizations, customers and related broker-dealers	1,822,549	304,022
Accrued commissions and other receivables, net	854,761	739,009
Loans, forgivable loans and other receivables from employees and partners, net	419,638	408,142
Fixed assets, net	211,233	214,782
Investments	40,004	38,008
Goodwill	556,392	556,211
Other intangible assets, net	281,571	287,157
Receivables from related parties	6,919	11,953
Other assets	485,837	480,418
Total assets	5,570,665	3,949,300
Liabilities, Redeemable Partnership Interest, and Equity
Short-term borrowings	3,510	3,849
Repurchase agreements	94
Accrued compensation	202,918	220,726
Payables to broker-dealers, clearing organizations, customers and related broker-dealers	1,676,985	179,716
Payables to related parties	47,501	36,252
Accounts payable, accrued and other liabilities	1,435,951	1,363,919
Notes payable and other borrowings	1,313,295	1,315,935
Total liabilities	4,680,254	3,120,397
Commitments, contingencies and guarantees (Note 19)
Redeemable partnership interest	19,989	20,674
Stockholders’ equity:
Additional paid-in capital	2,365,750	2,354,492
Treasury stock, at cost: 51,492 and 50,527 shares of Class A common stock at March 31, 2021 and December 31, 2020, respectively	(318,864)	(315,313)
Retained deficit	(1,226,187)	(1,265,504)
Accumulated other comprehensive income (loss)	(32,284)	(28,930)
Total stockholders’ equity	792,732	748,939
Noncontrolling interest in subsidiaries	77,690	59,290
Total equity	870,422	808,229
Total liabilities, redeemable partnership interest, and equity	5,570,665	3,949,300
Class A Common Stock [Member]
Stockholders’ equity:
Common stock value	3,858	3,735
Class B Common Stock [Member]
Stockholders’ equity:
Common stock value	$ 459	$ 459