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, 2023	Dec. 31, 2022	Dec. 31, 2021
Revenues:
Revenue from contracts with customers	$ 2,709,629	$ 2,950,827
Other sources of revenue:
Interest	1,955,745	1,099,115	$ 548,400
Principal transactions	490,440	529,033	581,164
Other Income	3,466	13,851
Total revenues	5,159,280	4,592,826	$ 4,783,086
Commissions [Member]
Revenues:
Revenue from contracts with customers	673,597	710,589
Investment Banking [Member]
Revenues:
Revenue from contracts with customers	731,255	971,485
Asset Management [Member]
Revenues:
Revenue from contracts with customers	1,299,496	1,262,919
Other [Member]
Revenues:
Revenue from contracts with customers	$ 5,281	$ 5,834