XML 57 R47.htm IDEA: XBRL DOCUMENT v3.21.2
Fair Value Measurements - Securities Owned and Securities Sold, But Not Yet Purchased at Fair Value (Details) - USD ($)
$ in Thousands
Jun. 30, 2021
Dec. 31, 2020
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]    
Securities owned, including amounts pledged of $0 ($546,334 in 2015), at fair value $ 544,062 $ 610,517
Securities Sold 112,838 126,171
Securities Owned and Sold, Not yet Purchased, at Fair Value, Security Owned, Including Disposal Group Securities Owned 544,062 610,517
Corporate debt and other obligations    
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]    
Securities owned, including amounts pledged of $0 ($546,334 in 2015), at fair value 20,621 23,977
Securities Sold 7,398 5,283
Municipal obligations    
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]    
Securities owned, including amounts pledged of $0 ($546,334 in 2015), at fair value 23,270 25,190
Convertible bonds    
Security Owned and Sold, Not yet Purchased, at Fair Value [Line Items]    
Securities owned, including amounts pledged of $0 ($546,334 in 2015), at fair value 23,312 $ 17,497
Securities Sold $ 6,739