Segment Information (Schedule Of Segment Reporting Information, By Segment) (Details) - USD ($) $ in Thousands	3 Months Ended
Feb. 29, 2020	Feb. 28, 2019
Segment Reporting Information [Line Items]
Net Revenues	$ 1,386,328	$ 828,443
Consolidated income before income taxes	157,794	49,317
Depreciation and amortization	39,470	33,934
Parent Company interest
Segment Reporting Information [Line Items]
Consolidated income before income taxes	(12,781)	(14,762)
Reportable Segments
Segment Reporting Information [Line Items]
Net Revenues	1,383,509	825,877
Consolidated income before income taxes	167,651	61,347
Reportable Segments \| Investment Banking and Capital Markets
Segment Reporting Information [Line Items]
Net Revenues	1,148,829	658,247
Consolidated income before income taxes	249,957	55,117
Depreciation and amortization	19,116	17,330
Reportable Segments \| Asset Management
Segment Reporting Information [Line Items]
Net Revenues	20,329	30,745
Consolidated income before income taxes	(20,929)	1,184
Depreciation and amortization	625	455
Reportable Segments \| Merchant Banking
Segment Reporting Information [Line Items]
Net Revenues	204,559	132,692
Consolidated income before income taxes	(53,623)	26,389
Depreciation and amortization	18,841	15,294
Reportable Segments \| Corporate
Segment Reporting Information [Line Items]
Net Revenues	9,792	4,193
Consolidated income before income taxes	(7,754)	(21,343)
Depreciation and amortization	888	855
Consolidation adjustments
Segment Reporting Information [Line Items]
Net Revenues	2,819	2,566
Consolidated income before income taxes	$ 2,924	$ 2,732

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income after deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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