v3.26.1
Revenues from Contracts with Customers (Revenues from Contracts with Customers Disaggregated by Major Business Activity and Primary Geographic Regions) (Details) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Disaggregation Of Revenue [Line Items]    
Commissions $ 207,834 $ 193,670
Investment banking 341,412 237,942
Total revenue from contracts with customers 1,010,359 842,490
Capital Raising [Member]    
Disaggregation Of Revenue [Line Items]    
Investment banking 122,974 100,472
Advisory [Member]    
Disaggregation Of Revenue [Line Items]    
Investment banking 218,438 137,470
Asset Management [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 459,457 409,541
Other [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 1,656 1,337
Global Wealth Management [Member]    
Disaggregation Of Revenue [Line Items]    
Commissions 140,064 125,826
Investment banking 6,072 5,908
Total revenue from contracts with customers 607,218 542,535
Global Wealth Management [Member] | Capital Raising [Member]    
Disaggregation Of Revenue [Line Items]    
Investment banking 6,072 5,908
Global Wealth Management [Member] | Asset Management [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 459,426 409,506
Global Wealth Management [Member] | Other [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 1,656 1,295
Institutional Group [Member]    
Disaggregation Of Revenue [Line Items]    
Commissions 67,770 67,844
Investment banking 335,340 232,034
Total revenue from contracts with customers 403,141 299,913
Institutional Group [Member] | Capital Raising [Member]    
Disaggregation Of Revenue [Line Items]    
Investment banking 116,902 94,564
Institutional Group [Member] | Advisory [Member]    
Disaggregation Of Revenue [Line Items]    
Investment banking 218,438 137,470
Institutional Group [Member] | Asset Management [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 31 35
Other [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers   42
Other [Member] | Other [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers   42
United States [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 919,584 783,079
United States [Member] | Global Wealth Management [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 607,218 542,535
United States [Member] | Institutional Group [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 312,366 240,502
United States [Member] | Other [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers   42
United Kingdom [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 52,237 35,564
United Kingdom [Member] | Institutional Group [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 52,237 35,564
Other [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 15,416 6,975
Other [Member] | Institutional Group [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 15,416 6,975
Canada [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers 23,122 16,872
Canada [Member] | Institutional Group [Member]    
Disaggregation Of Revenue [Line Items]    
Total revenue from contracts with customers $ 23,122 $ 16,872