v3.26.1
Fair Value Measurements - Not Measured at Fair Value (Details) - USD ($)
$ in Thousands
Mar. 31, 2026
Dec. 31, 2025
Mar. 31, 2025
Assets, not measured at fair value      
Cash and cash equivalents $ 1,024,459 $ 1,037,378 $ 1,229,181
Cash segregated under federal and other regulations 1,655,723 1,792,064 1,513,037
Restricted cash 225,765 225,298 $ 112,458
Receivables from clients, net 866,500 803,206  
Receivables from brokers, dealers and clearing organizations 100,003 70,897  
Advisor loans, net 3,741,085 3,681,512  
Other receivables, net 1,359,790 1,203,539  
Investment securities - held-to-maturity securities 15,460 15,420  
Other assets 2,220,909 2,202,444  
Liabilities, not measured at fair value      
Payables to clients 2,116,992 2,308,275  
Payables to broker-dealers and clearing organizations 307,677 150,520  
Corporate long-term debt 7,182,102 7,258,694  
Fair Value, Recurring      
Assets, not measured at fair value      
Restricted cash 127,227 127,585  
Other assets 1,458,051 1,471,620  
Other investments | Fair Value, Recurring      
Assets, not measured at fair value      
Other assets 1,810 2,423  
Deferred compensation plan | Fair Value, Recurring      
Assets, not measured at fair value      
Other assets 1,086,120 1,097,514  
Level 1 | Fair Value, Recurring      
Assets, not measured at fair value      
Restricted cash 127,227 127,585  
Other assets 1,456,241 1,469,197  
Level 1 | Other investments | Fair Value, Recurring      
Assets, not measured at fair value      
Other assets 0 0  
Level 1 | Deferred compensation plan | Fair Value, Recurring      
Assets, not measured at fair value      
Other assets 1,086,120 1,097,514  
Level 2 | Fair Value, Recurring      
Assets, not measured at fair value      
Restricted cash 0 0  
Other assets 1,810 2,423  
Level 2 | Other investments | Fair Value, Recurring      
Assets, not measured at fair value      
Other assets 1,810 2,423  
Level 2 | Deferred compensation plan | Fair Value, Recurring      
Assets, not measured at fair value      
Other assets 0 0  
Level 3 | Fair Value, Recurring      
Assets, not measured at fair value      
Restricted cash 0 0  
Other assets 0 0  
Level 3 | Other investments | Fair Value, Recurring      
Assets, not measured at fair value      
Other assets 0 0  
Level 3 | Deferred compensation plan | Fair Value, Recurring      
Assets, not measured at fair value      
Other assets 0 0  
Financial instruments not measured at fair value      
Assets, not measured at fair value      
Cash and cash equivalents 919,567 933,001  
Cash segregated under federal and other regulations 859,208 970,730  
Restricted cash 98,538 97,713  
Receivables from clients, net 866,500 803,206  
Receivables from brokers, dealers and clearing organizations 100,003 70,897  
Advisor loans, net 387,545 406,793  
Other receivables, net 1,359,790 1,203,539  
Investment securities - held-to-maturity securities 15,460 15,420  
Other assets 20,323 19,701  
Liabilities, not measured at fair value      
Payables to clients 2,116,992 2,308,275  
Payables to broker-dealers and clearing organizations 307,677 150,520  
Corporate long-term debt 7,182,102 7,258,694  
Financial instruments not measured at fair value | Other investments      
Assets, not measured at fair value      
Other assets 7,632 7,874  
Financial instruments not measured at fair value | Securities borrowed      
Assets, not measured at fair value      
Other assets 853 1,789  
Financial instruments not measured at fair value | Deferred compensation plan      
Assets, not measured at fair value      
Other assets 11,838 10,038  
Financial instruments not measured at fair value | Total Fair Value      
Assets, not measured at fair value      
Cash and cash equivalents 919,567 933,001  
Cash segregated under federal and other regulations 859,208 970,730  
Restricted cash 98,538 97,713  
Receivables from clients, net 866,500 803,206  
Receivables from brokers, dealers and clearing organizations 100,003 70,897  
Advisor loans, net 328,975 335,050  
Other receivables, net 1,359,790 1,203,539  
Investment securities - held-to-maturity securities 15,477 15,520  
Other assets 20,323 19,701  
Liabilities, not measured at fair value      
Payables to clients 2,116,992 2,308,275  
Payables to broker-dealers and clearing organizations 307,677 150,520  
Corporate long-term debt 7,226,449 7,420,447  
Financial instruments not measured at fair value | Total Fair Value | Other investments      
Assets, not measured at fair value      
Other assets 7,632 7,874  
Financial instruments not measured at fair value | Total Fair Value | Securities borrowed      
Assets, not measured at fair value      
Other assets 853 1,789  
Financial instruments not measured at fair value | Total Fair Value | Deferred compensation plan      
Assets, not measured at fair value      
Other assets 11,838 10,038  
Financial instruments not measured at fair value | Level 1      
Assets, not measured at fair value      
Cash and cash equivalents 919,567 933,001  
Cash segregated under federal and other regulations 859,208 970,730  
Restricted cash 98,538 97,713  
Receivables from clients, net 0 0  
Receivables from brokers, dealers and clearing organizations 0 0  
Advisor loans, net 0 0  
Other receivables, net 0 0  
Investment securities - held-to-maturity securities 0 0  
Other assets 11,838 10,038  
Liabilities, not measured at fair value      
Payables to clients 0 0  
Payables to broker-dealers and clearing organizations 0 0  
Corporate long-term debt 0 0  
Financial instruments not measured at fair value | Level 1 | Other investments      
Assets, not measured at fair value      
Other assets 0 0  
Financial instruments not measured at fair value | Level 1 | Securities borrowed      
Assets, not measured at fair value      
Other assets 0 0  
Financial instruments not measured at fair value | Level 1 | Deferred compensation plan      
Assets, not measured at fair value      
Other assets 11,838 10,038  
Financial instruments not measured at fair value | Level 2      
Assets, not measured at fair value      
Cash and cash equivalents 0 0  
Cash segregated under federal and other regulations 0 0  
Restricted cash 0 0  
Receivables from clients, net 866,500 803,206  
Receivables from brokers, dealers and clearing organizations 100,003 70,897  
Advisor loans, net 0 0  
Other receivables, net 1,359,790 1,203,539  
Investment securities - held-to-maturity securities 15,477 15,520  
Other assets 8,485 9,663  
Liabilities, not measured at fair value      
Payables to clients 2,116,992    
Payables to broker-dealers and clearing organizations 307,677    
Corporate long-term debt 7,226,449 7,420,447  
Financial instruments not measured at fair value | Level 2 | Other investments      
Assets, not measured at fair value      
Other assets 7,632 7,874  
Financial instruments not measured at fair value | Level 2 | Securities borrowed      
Assets, not measured at fair value      
Other assets 853 1,789  
Financial instruments not measured at fair value | Level 2 | Deferred compensation plan      
Assets, not measured at fair value      
Other assets 0 0  
Financial instruments not measured at fair value | Level 3      
Assets, not measured at fair value      
Cash and cash equivalents 0 0  
Cash segregated under federal and other regulations 0 0  
Restricted cash 0 0  
Receivables from clients, net 0 0  
Receivables from brokers, dealers and clearing organizations 0 0  
Advisor loans, net 328,975 335,050  
Other receivables, net 0 0  
Investment securities - held-to-maturity securities 0 0  
Other assets 0 0  
Liabilities, not measured at fair value      
Payables to clients 0 0  
Payables to broker-dealers and clearing organizations 0 0  
Corporate long-term debt 0 0  
Financial instruments not measured at fair value | Level 3 | Other investments      
Assets, not measured at fair value      
Other assets 0 0  
Financial instruments not measured at fair value | Level 3 | Securities borrowed      
Assets, not measured at fair value      
Other assets 0 0  
Financial instruments not measured at fair value | Level 3 | Deferred compensation plan      
Assets, not measured at fair value      
Other assets $ 0 $ 0