Segment Operating Results - (Footnotes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Segment Reporting Information [Line Items]
Other Revenue, net	$ (24,228)	$ 19,196	$ (28,648)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax			20,337
Special Charges, Including Business Realignment Costs	3,126	8,554	46,645
Acquisition and Transition Costs	0	7	562
Total Other Expenses	3,126	8,561	49,457
Investment Banking and Equities [Member]
Segment Reporting Information [Line Items]
Other Revenue, net	(25,668)	19,370	(20,770)
Interest expense on Notes Payable and Line of Credit	16,850	17,586	18,197
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax			21,070
Amortization of LP Units and Certain Other Awards	0	0	1,067
Special Charges, Including Business Realignment Costs	3,126	0	46,600
Acquisition and Transition Costs	0	7	262
Intangible Asset and Other Amortization	0	0	1,183
Total Other Expenses	3,126	7	49,112
Investment Management [Member]
Segment Reporting Information [Line Items]
Other Revenue, net	1,440	(174)	(7,878)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax			6,295
Net Loss on Sale and Wind-down of Operations in Mexico in 2020 and Release of Cumulative Foreign Exchange Losses			3,441
Special Charges, Including Business Realignment Costs	0	8,554	45
Acquisition and Transition Costs	0	0	300
Total Other Expenses	$ 0	$ 8,554	$ 345