Revenues from Contracts with Customers (Schedule of Total Revenues Broken Out by Revenues from Contracts with Customers and Other Sources of Revenues) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Revenues:
Revenue from contracts with customers	$ 2,950,827	$ 3,615,636
Other sources of revenue:
Interest	1,099,115	548,400	$ 523,832
Principal transactions	529,033	581,164	588,303
Other Income	13,851	37,886
Total revenues	4,592,826	4,783,086	$ 3,817,839
Commissions [Member]
Revenues:
Revenue from contracts with customers	710,589	809,500
Investment Banking [Member]
Revenues:
Revenue from contracts with customers	971,485	1,565,381
Asset Management [Member]
Revenues:
Revenue from contracts with customers	1,262,919	1,206,516
Other [Member]
Revenues:
Revenue from contracts with customers	$ 5,834	$ 34,239