Revenues From Contracts With Customers (Revenues From Contracts With Customers Disaggregated by Major Business Activity and Primary Geographic Regions) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Disaggregation Of Revenue [Line Items]
Commissions	$ 756,024	$ 673,597
Investment banking	994,831	731,255
Revenue from contracts with customers	3,293,976	2,709,629
Capital Raising [Member]
Disaggregation Of Revenue [Line Items]
Investment banking	417,399	265,667
Advisory [Member]
Disaggregation Of Revenue [Line Items]
Investment banking	577,432	465,588
Asset Management [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	1,536,674	1,299,496
Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	6,447	5,281
Global Wealth Management [Member]
Disaggregation Of Revenue [Line Items]
Commissions	508,717	444,949
Investment banking	21,475	16,680
Revenue from contracts with customers	2,072,886	1,766,069
Global Wealth Management [Member] \| Capital Raising [Member]
Disaggregation Of Revenue [Line Items]
Investment banking	21,475	16,680
Global Wealth Management [Member] \| Asset Management [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	1,536,296	1,299,361
Global Wealth Management [Member] \| Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	6,398	5,079
Institutional Group [Member]
Disaggregation Of Revenue [Line Items]
Commissions	247,307	228,648
Investment banking	973,356	714,575
Revenue from contracts with customers	1,221,041	943,375
Institutional Group [Member] \| Capital Raising [Member]
Disaggregation Of Revenue [Line Items]
Investment banking	395,924	248,987
Institutional Group [Member] \| Advisory [Member]
Disaggregation Of Revenue [Line Items]
Investment banking	577,432	465,588
Institutional Group [Member] \| Asset Management [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	378	135
Institutional Group [Member] \| Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers		17
Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	49	185
Other [Member] \| Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	49	185
United States [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	3,073,094	2,507,537
United States [Member] \| Global Wealth Management [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	2,072,886	1,766,069
United States [Member] \| Institutional Group [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	1,000,159	741,283
United States [Member] \| Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	49	185
United Kingdom [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	127,113	107,631
United Kingdom [Member] \| Institutional Group [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	127,113	107,631
Canada [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	40,000	42,263
Canada [Member] \| Institutional Group [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	40,000	42,263
Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	53,769	52,198
Other [Member] \| Institutional Group [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	$ 53,769	$ 52,198

Amount of commission revenue from buying and selling securities on behalf of customers.

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