Collateralized Transactions (Collateral Pledged) (Details) - USD ($) $ in Thousands	May 31, 2020	Nov. 30, 2019
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	$ 1,941,468	$ 1,525,140
Repurchase agreements	19,948,192	18,756,917
Obligation to return securities received as collateral, at fair value	9,909	9,500
Total	21,899,569	20,291,557
Corporate equity securities
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	1,361,027	1,314,395
Repurchase agreements	19,560	129,558
Obligation to return securities received as collateral, at fair value	0	0
Total	1,380,587	1,443,953
Corporate debt securities
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	574,834	191,311
Repurchase agreements	1,774,184	1,730,526
Obligation to return securities received as collateral, at fair value	0	0
Total	2,349,018	1,921,837
Mortgage-backed and asset-backed securities
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	0	0
Repurchase agreements	1,604,243	1,745,145
Obligation to return securities received as collateral, at fair value	0	0
Total	1,604,243	1,745,145
U.S. government and federal agency securities
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	5,607	19,434
Repurchase agreements	10,924,983	10,863,997
Obligation to return securities received as collateral, at fair value	9,909	9,500
Total	10,940,499	10,892,931
Municipal securities
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	0	0
Repurchase agreements	359,159	498,202
Obligation to return securities received as collateral, at fair value	0	0
Total	359,159	498,202
Sovereign obligations
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	0	0
Repurchase agreements	4,138,647	3,016,563
Obligation to return securities received as collateral, at fair value	0	0
Total	4,138,647	3,016,563
Loans and other receivables
Transfer of Certain Financial Assets Accounted for as Secured Borrowings [Line Items]
Securities lending arrangements	0	0
Repurchase agreements	1,127,416	772,926
Obligation to return securities received as collateral, at fair value	0	0
Total	$ 1,127,416	$ 772,926

Amount, before effects of master netting arrangements, of funds outstanding borrowed in the form of a financial asset repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same financial asset at a date certain for a specified price. Includes repurchase-to-maturity transactions and liabilities not subject to a master netting arrangement.

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- Definition

The fair value of collateral received by the entity associated with securities borrowed that must be returned if the counterparty fulfills its obligations. It appears on the balance sheet as a liability and has a corresponding asset that appears on the balance sheet called Securities Received as Collateral.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.15)
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

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- Definition

Amount, before effects of master netting arrangements, of financial assets loaned to entities in exchange for collateral and funds outstanding borrowed in the form of a financial asset repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same financial assets at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

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- Definition

Amount, before effects of master netting arrangements, of financial assets loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and financial assets transferred other than securities that qualify as secured borrowings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 7
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL34722452-111729

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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