Segment Information - Reported Revenue and Profit Before Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenue
Total revenue	$ (234,793)	$ (237,814)	$ (737,498)	$ (714,900)
Income (loss) before income taxes
Operating Income (Loss)	6,496	7,154	39,939	29,292
Private Client Division
Revenue
Total revenue	(152,054)	(158,083)	(477,509)	(468,730)
Income (loss) before income taxes
Income before income taxes	$ 35,251	37,608	121,501	111,283
Asset management fees	90.00%
Asset Management
Revenue
Total revenue	$ (18,368)	(17,870)	(53,576)	(53,220)
Income (loss) before income taxes
Income before income taxes	$ 4,932	4,127	12,492	11,803
Asset management fees	10.00%
Capital markets
Revenue
Total revenue	$ (64,068)	(68,130)	(206,848)	(197,865)
Income (loss) before income taxes
Income before income taxes	(6,385)	(2,076)	(10,833)	(8,332)
Corporate/Other
Revenue
Total revenue	(303)	6,269	435	4,915
Income (loss) before income taxes
Income before income taxes	$ (27,302)	$ (32,505)	$ (83,221)	$ (85,462)