Collateralized Transactions - Gross Secured Financing Balances (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Gross Secured Financing Balances
Securities sold under agreements to repurchase	$ 229,626	$ 214,213
Securities loaned	19,967	30,306
Total included in the offsetting disclosure	249,593	244,519
Trading liabilities— Obligation to return securities received as collateral	21,440	17,594
Total	271,033	262,113
U.S. Treasury and agency securities
Gross Secured Financing Balances
Securities sold under agreements to repurchase	81,642	68,487
State and municipal securities
Gross Secured Financing Balances
Securities sold under agreements to repurchase	1,164	925
Other sovereign government obligations
Gross Secured Financing Balances
Securities sold under agreements to repurchase	117,949	120,432
Securities loaned	10,667	19,021
ABS
Gross Secured Financing Balances
Securities sold under agreements to repurchase	2,338	3,017
Corporate and other debt
Gross Secured Financing Balances
Securities sold under agreements to repurchase	7,718	8,719
Corporate equities
Gross Secured Financing Balances
Securities sold under agreements to repurchase	18,279	12,079
Securities loaned	9,242	10,800
Trading liabilities— Obligation to return securities received as collateral	21,432	17,594
Other
Gross Secured Financing Balances
Securities sold under agreements to repurchase	536	554
Securities loaned	58	485
Trading liabilities— Obligation to return securities received as collateral	8	0
Overnight and Open
Gross Secured Financing Balances
Securities sold under agreements to repurchase	78,896	56,503
Securities loaned	9,780	18,397
Total included in the offsetting disclosure	88,676	74,900
Trading liabilities— Obligation to return securities received as collateral	21,440	17,594
Total	110,116	92,494
Less than 30 Days
Gross Secured Financing Balances
Securities sold under agreements to repurchase	74,832	93,427
Securities loaned	4,540	3,609
Total included in the offsetting disclosure	79,372	97,036
Trading liabilities— Obligation to return securities received as collateral	0	0
Total	79,372	97,036
30-90 Days
Gross Secured Financing Balances
Securities sold under agreements to repurchase	31,794	35,692
Securities loaned	611	1,985
Total included in the offsetting disclosure	32,405	37,677
Trading liabilities— Obligation to return securities received as collateral	0	0
Total	32,405	37,677
Over 90 Days
Gross Secured Financing Balances
Securities sold under agreements to repurchase	44,104	28,591
Securities loaned	5,036	6,315
Total included in the offsetting disclosure	49,140	34,906
Trading liabilities— Obligation to return securities received as collateral	0	0
Total	$ 49,140	$ 34,906

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