Collateralized Transactions - Collateral Pledged (Details) - USD ($) $ in Thousands	Feb. 28, 2021	Nov. 30, 2020
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	$ 2,519,077	$ 1,810,748
Repurchase Agreements	16,859,028	15,159,273
Obligation To Return Securities Received As Collateral, at fair value		7,517
Total	19,378,105	16,977,538
Corporate equity securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	2,067,474	1,371,978
Repurchase Agreements	245,823	157,912
Obligation To Return Securities Received As Collateral, at fair value		7,517
Total	2,313,297	1,537,407
Corporate debt securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	372,966	369,218
Repurchase Agreements	2,113,427	1,869,844
Obligation To Return Securities Received As Collateral, at fair value		0
Total	2,486,393	2,239,062
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	1,378,273	1,547,140
Obligation To Return Securities Received As Collateral, at fair value		0
Total	1,378,273	1,547,140
U.S. government and federal agency securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	20,353	14,789
Repurchase Agreements	9,417,370	7,149,992
Obligation To Return Securities Received As Collateral, at fair value		0
Total	9,437,723	7,164,781
Municipal securities
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	138,344	278,470
Obligation To Return Securities Received As Collateral, at fair value		0
Total	138,344	278,470
Sovereign obligations
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	58,284	54,763
Repurchase Agreements	2,584,304	2,763,032
Obligation To Return Securities Received As Collateral, at fair value		0
Total	2,642,588	2,817,795
Loans and other receivables
Transfer Of Certain Financial Assets Accounted For As Secured Borrowings [Line Items]
Securities Lending Arrangements	0	0
Repurchase Agreements	981,487	1,392,883
Obligation To Return Securities Received As Collateral, at fair value		0
Total	$ 981,487	$ 1,392,883

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
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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