Collateralized Transactions - Collateral Pledged (Details) - USD ($) $ in Thousands	Aug. 31, 2018	Nov. 30, 2017
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	$ 2,531,504	$ 2,843,911
Repurchase Agreements	17,839,459	19,829,249
Obligation To Return Securities Received As Collateral		103
Total	20,370,963	22,673,263
Cash
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0
Repurchase Agreements	4,361
Total	4,361
Corporate equity securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	2,214,433	2,353,798
Repurchase Agreements	490,609	214,413
Obligation To Return Securities Received As Collateral		0
Total	2,705,042	2,568,211
Corporate debt securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	315,718	470,908
Repurchase Agreements	1,496,127	2,336,702
Obligation To Return Securities Received As Collateral		0
Total	1,811,845	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	2,667,439	2,562,268
Obligation To Return Securities Received As Collateral		0
Total	2,667,439	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	1,353	19,205
Repurchase Agreements	10,124,642	11,792,534
Obligation To Return Securities Received As Collateral		0
Total	10,125,995	11,811,739
Municipal securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	582,699	444,861
Obligation To Return Securities Received As Collateral		0
Total	582,699	444,861
Sovereign obligations
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	1,955,879	2,023,530
Obligation To Return Securities Received As Collateral		103
Total	1,955,879	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	517,703	454,941
Obligation To Return Securities Received As Collateral		0
Total	$ 517,703	$ 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
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