Revenues from Contracts with Customers (Schedule of Components of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	May 31, 2020	May 31, 2019	May 31, 2020	May 31, 2019
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 749,919	$ 750,014	$ 1,662,735	$ 1,320,014
Other sources of revenue	627,612	760,357	1,407,060	1,385,369
Total revenues	1,377,531	1,510,371	3,069,795	2,705,383
Commissions and other fees
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	242,972	167,610	422,402	322,560
Total revenues	242,972	167,610	422,402	322,560
Investment banking
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	387,491	430,087	979,493	715,683
Total revenues	387,491	430,087	979,493	715,683
Manufacturing revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	85,379	90,237	162,986	165,662
Total revenues	85,379	90,237	162,986	165,662
Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	34,077	62,080	97,854	116,109
Principal transactions
Disaggregation of Revenue [Line Items]
Other sources of revenue	393,338	240,189	798,202	486,371
Total revenues	393,338	240,189	798,202	486,371
Interest income
Disaggregation of Revenue [Line Items]
Other sources of revenue	236,732	445,967	563,098	832,811
Total revenues	236,732	445,967	563,098	832,811
Other
Disaggregation of Revenue [Line Items]
Other sources of revenue	$ (2,458)	$ 74,201	$ 45,760	$ 66,187