Revenues from Contracts with Customers - Components of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Feb. 29, 2020	Feb. 28, 2019
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 775,941	$ 447,407
Principal transactions	371,902	234,298
Revenues from arrangements with strategic partners	7,316	362
Interest	294,668	360,975
Other	29,729	11,830
Total revenues	1,479,556	1,054,872
Commissions and other fees
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	179,535	155,142
Investment banking
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	592,002	285,596
Asset management and revenues
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 4,404	$ 6,669

Other Revenue, Revenue From Arrangements With Strategic Partners

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