Variable Interest Entities - Firm Sponsored VIEs (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Firm-sponsored mortgage and other consumer securitization trusts
Total assets held by securitization VIEs	$ 178,260	$ 183,040
Retained securitization interests, risk-rated 'A' or better, at fair value	67.00%	60.00%
Corporate & Investment Bank
Firm-sponsored mortgage and other consumer securitization trusts
Senior securities purchased in connection with CIB's secondary market-making activities	$ 168	$ 87
Subordinated securities purchased in connection with CIB's secondary market-making activities	69	28
Residential mortgage \| Investment-grade
Firm-sponsored mortgage and other consumer securitization trusts
Fair value of retained interests	1,200	1,300
Residential mortgage \| Noninvestment-grade
Firm-sponsored mortgage and other consumer securitization trusts
Fair value of retained interests	55	16
Residential mortgage \| Prime / Alt-A & option ARMs
Firm-sponsored mortgage and other consumer securitization trusts
Total assets held by securitization VIEs	61,480	63,350
Residential mortgage \| Subprime
Firm-sponsored mortgage and other consumer securitization trusts
Total assets held by securitization VIEs	15,156	16,729
Commercial and other
Firm-sponsored mortgage and other consumer securitization trusts
Total assets held by securitization VIEs	101,624	102,961
Commercial and other \| Investment-grade
Firm-sponsored mortgage and other consumer securitization trusts
Fair value of retained interests	1,300	1,200
Commercial and other \| Noninvestment-grade
Firm-sponsored mortgage and other consumer securitization trusts
Fair value of retained interests	567	623
VIEs consolidated by the Firm
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in consolidated securitization VIEs	2,966	3,269
VIEs consolidated by the Firm \| Residential mortgage \| Prime / Alt-A & option ARMs
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in consolidated securitization VIEs	2,966	3,237
VIEs consolidated by the Firm \| Residential mortgage \| Subprime
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in consolidated securitization VIEs	0	32
VIEs consolidated by the Firm \| Commercial and other
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in consolidated securitization VIEs	0	0
Nonconsolidated re-securitization VIEs
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in nonconsolidated securitization VIEs with continuing involvement	150,213	145,500
Interest in securitized assets in nonconsolidated VIEs	3,127	3,117
Nonconsolidated re-securitization VIEs \| Trading assets
Firm-sponsored mortgage and other consumer securitization trusts
Interest in securitized assets in nonconsolidated VIEs	1,457	1,459
Nonconsolidated re-securitization VIEs \| Investment securities
Firm-sponsored mortgage and other consumer securitization trusts
Interest in securitized assets in nonconsolidated VIEs	1,436	1,448
Nonconsolidated re-securitization VIEs \| Other financial assets
Firm-sponsored mortgage and other consumer securitization trusts
Interest in securitized assets in nonconsolidated VIEs	234	210
Nonconsolidated re-securitization VIEs \| Residential mortgage \| Prime / Alt-A & option ARMs
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in nonconsolidated securitization VIEs with continuing involvement	49,826	50,679
Interest in securitized assets in nonconsolidated VIEs	1,250	1,270
Nonconsolidated re-securitization VIEs \| Residential mortgage \| Subprime
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in nonconsolidated securitization VIEs with continuing involvement	14,085	15,434
Interest in securitized assets in nonconsolidated VIEs	16	53
Nonconsolidated re-securitization VIEs \| Residential mortgage \| Trading assets \| Prime / Alt-A & option ARMs
Firm-sponsored mortgage and other consumer securitization trusts
Interest in securitized assets in nonconsolidated VIEs	522	623
Nonconsolidated re-securitization VIEs \| Residential mortgage \| Trading assets \| Subprime
Firm-sponsored mortgage and other consumer securitization trusts
Interest in securitized assets in nonconsolidated VIEs	16	53
Nonconsolidated re-securitization VIEs \| Residential mortgage \| Investment securities \| Prime / Alt-A & option ARMs
Firm-sponsored mortgage and other consumer securitization trusts
Interest in securitized assets in nonconsolidated VIEs	728	647
Nonconsolidated re-securitization VIEs \| Residential mortgage \| Investment securities \| Subprime
Firm-sponsored mortgage and other consumer securitization trusts
Interest in securitized assets in nonconsolidated VIEs	0	0
Nonconsolidated re-securitization VIEs \| Residential mortgage \| Other financial assets \| Prime / Alt-A & option ARMs
Firm-sponsored mortgage and other consumer securitization trusts
Interest in securitized assets in nonconsolidated VIEs	0	0
Nonconsolidated re-securitization VIEs \| Residential mortgage \| Other financial assets \| Subprime
Firm-sponsored mortgage and other consumer securitization trusts
Interest in securitized assets in nonconsolidated VIEs	0	0
Nonconsolidated re-securitization VIEs \| Commercial and other
Firm-sponsored mortgage and other consumer securitization trusts
Assets held in nonconsolidated securitization VIEs with continuing involvement	86,302	79,387
Interest in securitized assets in nonconsolidated VIEs	1,861	1,794
Nonconsolidated re-securitization VIEs \| Commercial and other \| Trading assets
Firm-sponsored mortgage and other consumer securitization trusts
Interest in securitized assets in nonconsolidated VIEs	919	783
Nonconsolidated re-securitization VIEs \| Commercial and other \| Investment securities
Firm-sponsored mortgage and other consumer securitization trusts
Interest in securitized assets in nonconsolidated VIEs	708	801
Nonconsolidated re-securitization VIEs \| Commercial and other \| Other financial assets
Firm-sponsored mortgage and other consumer securitization trusts
Interest in securitized assets in nonconsolidated VIEs	$ 234	$ 210

Firm-sponsored mortgage and other consumer securitization trusts.

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Percent of retained securitization interests rated A or better.

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Senior securities purchased in connection with IB secondary market making activities. These securities are excluded from entity interest in securitized assets in nonconsolidated VIEs.

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Subordinated securities purchased in connection with IB secondary market making Activities. These securities are excluded from entity interest in securitized assets in nonconsolidated VIEs.

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No definition available.

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Principal amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

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