Collateralized Transactions - Collateral Pledged (Details) - USD ($) $ in Thousands	May 31, 2018	Nov. 30, 2017
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	$ 2,555,701	$ 2,843,911
Repurchase Agreements	17,057,241	19,829,249
Obligation To Return Securities Received As Collateral		103
Total	19,612,942	22,673,263
Corporate equity securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	2,210,311	2,353,798
Repurchase Agreements	430,084	214,413
Obligation To Return Securities Received As Collateral		0
Total	2,640,395	2,568,211
Corporate debt securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	343,068	470,908
Repurchase Agreements	1,999,524	2,336,702
Obligation To Return Securities Received As Collateral		0
Total	2,342,592	2,807,610
Mortgage- and asset-backed securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	3,179,689	2,562,268
Obligation To Return Securities Received As Collateral		0
Total	3,179,689	2,562,268
U.S. government and federal agency securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	2,322	19,205
Repurchase Agreements	7,938,208	11,792,534
Obligation To Return Securities Received As Collateral		0
Total	7,940,530	11,811,739
Municipal securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	550,030	444,861
Obligation To Return Securities Received As Collateral		0
Total	550,030	444,861
Sovereign obligations
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	2,419,766	2,023,530
Obligation To Return Securities Received As Collateral		103
Total	2,419,766	2,023,633
Loans and other receivables
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	539,940	454,941
Obligation To Return Securities Received As Collateral		0
Total	$ 539,940	$ 454,941

Amount, after effects of master netting arrangements, of derivative liabilities, securities sold under agreements to repurchase and securities loaned offset against a right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 30
-Section 50
-Paragraph 7
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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