Collateralized Transactions - Gross Secured Financing Balances (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Gross Secured Financing Balances
Securities sold under agreements to repurchase	$ 226,900	$ 214,213
Securities loaned	19,791	30,306
Total included in the offsetting disclosure	246,691	244,519
Trading liabilities— Obligation to return securities received as collateral	20,001	17,594
Total	266,692	262,113
U.S. Treasury and agency securities
Gross Secured Financing Balances
Securities sold under agreements to repurchase	78,757	68,487
State and municipal securities
Gross Secured Financing Balances
Securities sold under agreements to repurchase	1,417	925
Other sovereign government obligations
Gross Secured Financing Balances
Securities sold under agreements to repurchase	120,426	120,432
Securities loaned	9,904	19,021
ABS
Gross Secured Financing Balances
Securities sold under agreements to repurchase	1,634	3,017
Corporate and other debt
Gross Secured Financing Balances
Securities sold under agreements to repurchase	7,265	8,719
Corporate equities
Gross Secured Financing Balances
Securities sold under agreements to repurchase	16,562	12,079
Securities loaned	9,800	10,800
Trading liabilities— Obligation to return securities received as collateral	20,001	17,594
Other
Gross Secured Financing Balances
Securities sold under agreements to repurchase	839	554
Securities loaned	87	485
Overnight and Open
Gross Secured Financing Balances
Securities sold under agreements to repurchase	86,201	56,503
Securities loaned	12,314	18,397
Total included in the offsetting disclosure	98,515	74,900
Trading liabilities— Obligation to return securities received as collateral	20,001	17,594
Total	118,516	92,494
Less than 30 Days
Gross Secured Financing Balances
Securities sold under agreements to repurchase	68,956	93,427
Securities loaned	1,595	3,609
Total included in the offsetting disclosure	70,551	97,036
Trading liabilities— Obligation to return securities received as collateral	0	0
Total	70,551	97,036
30-90 Days
Gross Secured Financing Balances
Securities sold under agreements to repurchase	29,202	35,692
Securities loaned	1,196	1,985
Total included in the offsetting disclosure	30,398	37,677
Trading liabilities— Obligation to return securities received as collateral	0	0
Total	30,398	37,677
Over 90 Days
Gross Secured Financing Balances
Securities sold under agreements to repurchase	42,541	28,591
Securities loaned	4,686	6,315
Total included in the offsetting disclosure	47,227	34,906
Trading liabilities— Obligation to return securities received as collateral	0	0
Total	$ 47,227	$ 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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