Concentrations of Credit Risk (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Risks and Uncertainties [Abstract]
Investment Banking And Investment Management Receivables Collection Periods	90 days
Placement Fees Receivables Collection Period	180 days
Private Funds Capital Raising and Private Capital Receivables Collection Period	1 year
Restructuring Receivables Collection Period	90 days
Receivables Reflected in Other Assets in Excess of Period	1 year
Accounts Receivable, after Allowance for Credit Loss	$ 371,606	$ 385,131
Contract with Customer, Receivable, Net, Noncurrent	93,689	64,139	$ 87,764
Bad Debt Expense	5,559	5,513	(60)
Contract with Customer, Asset, Gross, Current	85,401	110,468	14,092
Contract with Customer, Asset, Gross, Noncurrent	5,845	8,028	$ 12,945
Investment Securities	$ 1,382,027	1,309,826
Percentage Of Marketable Securities Related To U.S. Treasury Bills and Notes	88.00%
Percentage Of Marketable Securities Related To Equity Securities and Exchange Traded Funds	12.00%
Certificates of Deposit, at Carrying Value	$ 54,856	$ 122,890