Segment Information - Reported Revenue and Profit Before Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Revenue
Total revenue	$ (373,282)	$ (234,770)
Income (loss) before income taxes
Operating Income (Loss)	52,127	10,223
Private Client Division
Revenue
Total revenue	(164,023)	(141,418)
Income (loss) before income taxes
Income before income taxes	$ 24,263	33,369
Asset management fees	90.00%
Asset Management
Revenue
Total revenue	$ (24,230)	(19,276)
Income (loss) before income taxes
Income before income taxes	$ 7,553	4,305
Asset management fees	10.00%
Capital markets
Revenue
Total revenue	$ (183,599)	(75,542)
Income (loss) before income taxes
Income before income taxes	49,991	(143)
Corporate/Other
Revenue
Total revenue	(1,430)	1,466
Income (loss) before income taxes
Income before income taxes	$ (29,680)	$ (27,308)

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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