Collateralized Transactions - Gross Secured Financing Balances (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Gross Secured Financing Balances
Securities sold under agreements to repurchase	$ 155,497	$ 198,493
Securities loaned	19,765	20,261
Total included in the offsetting disclosure	175,262	218,754
Trading liabilities— Obligation to return securities received as collateral	18,877	16,389
Total	194,139	235,143
U.S. Treasury and agency securities
Gross Secured Financing Balances
Securities sold under agreements to repurchase	50,124	94,662
Other sovereign government obligations
Gross Secured Financing Balances
Securities sold under agreements to repurchase	71,250	71,140
Securities loaned	2,642	3,430
Corporate equities
Gross Secured Financing Balances
Securities sold under agreements to repurchase	22,618	24,692
Securities loaned	17,027	16,536
Trading liabilities— Obligation to return securities received as collateral	18,859	16,365
Other
Gross Secured Financing Balances
Securities sold under agreements to repurchase	11,505	7,999
Securities loaned	96	295
Trading liabilities— Obligation to return securities received as collateral	18	24
Overnight and Open
Gross Secured Financing Balances
Securities sold under agreements to repurchase	52,398	84,349
Securities loaned	13,850	15,267
Total included in the offsetting disclosure	66,248	99,616
Trading liabilities— Obligation to return securities received as collateral	18,877	16,389
Total	85,125	116,005
Less than 30 Days
Gross Secured Financing Balances
Securities sold under agreements to repurchase	49,603	60,853
Securities loaned	0	247
Total included in the offsetting disclosure	49,603	61,100
Trading liabilities— Obligation to return securities received as collateral	0	0
Total	49,603	61,100
30-90 Days
Gross Secured Financing Balances
Securities sold under agreements to repurchase	14,078	26,221
Securities loaned	59	0
Total included in the offsetting disclosure	14,137	26,221
Trading liabilities— Obligation to return securities received as collateral	0	0
Total	14,137	26,221
Over 90 Days
Gross Secured Financing Balances
Securities sold under agreements to repurchase	39,418	27,070
Securities loaned	5,856	4,747
Total included in the offsetting disclosure	45,274	31,817
Trading liabilities— Obligation to return securities received as collateral	0	0
Total	$ 45,274	$ 31,817

The aggregate amount of liabilities as of the balance sheet date for obligations incurred in connection with the entity's investments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-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

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