Variable Interest Entities and Securitization Activities (Transfers of Assets with Continuing Involvement 1) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Variable Interest Entity
Derivative assets (fair value)	$ 33,294	$ 36,394
Derivative liabilities (fair value)	35,773	40,212
Special Purpose Entities
Variable Interest Entity
Retained interests (fair value)	2,906	2,685
Interests purchased in the secondary market (fair value)	641	808
Derivative assets (fair value)	493	633
Derivative liabilities (fair value)	780	86
Special Purpose Entities \| Investment Grade
Variable Interest Entity
Retained interests (fair value)	1,440	1,203
Interests purchased in the secondary market (fair value)	437	645
Special Purpose Entities \| Noninvestment Grade
Variable Interest Entity
Retained interests (fair value)	1,466	1,482
Interests purchased in the secondary market (fair value)	204	163
Special Purpose Entities \| Residential Mortgage
Variable Interest Entity
SPE assets (unpaid principal balance)	24,523	26,549
Retained interests (fair value)	203	108
Interests purchased in the secondary market (fair value)	92	64
Derivative assets (fair value)	0	0
Derivative liabilities (fair value)	0	0
Special Purpose Entities \| Residential Mortgage \| Investment Grade
Variable Interest Entity
Retained interests (fair value)	0	10
Interests purchased in the secondary market (fair value)	0	32
Special Purpose Entities \| Residential Mortgage \| Noninvestment Grade
Variable Interest Entity
Retained interests (fair value)	203	98
Interests purchased in the secondary market (fair value)	92	32
Special Purpose Entities \| Commercial Mortgage Loans
Variable Interest Entity
SPE assets (unpaid principal balance)	58,983	58,660
Retained interests (fair value)	219	237
Interests purchased in the secondary market (fair value)	312	201
Derivative assets (fair value)	376	495
Derivative liabilities (fair value)	0	0
Special Purpose Entities \| Commercial Mortgage Loans \| Investment Grade
Variable Interest Entity
Retained interests (fair value)	150	117
Interests purchased in the secondary market (fair value)	231	129
Special Purpose Entities \| Commercial Mortgage Loans \| Noninvestment Grade
Variable Interest Entity
Retained interests (fair value)	69	120
Interests purchased in the secondary market (fair value)	81	72
Special Purpose Entities \| U.S. Agency Collateralized Mortgage Obligations
Variable Interest Entity
SPE assets (unpaid principal balance)	19,020	20,826
Retained interests (fair value)	1,290	1,019
Interests purchased in the secondary market (fair value)	204	61
Derivative assets (fair value)	0	0
Derivative liabilities (fair value)	0	0
Special Purpose Entities \| U.S. Agency Collateralized Mortgage Obligations \| Investment Grade
Variable Interest Entity
Retained interests (fair value)	1,290	1,019
Interests purchased in the secondary market (fair value)	204	61
Special Purpose Entities \| U.S. Agency Collateralized Mortgage Obligations \| Noninvestment Grade
Variable Interest Entity
Retained interests (fair value)	0	0
Interests purchased in the secondary market (fair value)	0	0
Special Purpose Entities \| Credit-Linked Notes and Other
Variable Interest Entity
SPE assets (unpaid principal balance)	20,296	24,011
Retained interests (fair value)	1,194	1,321
Interests purchased in the secondary market (fair value)	33	482
Derivative assets (fair value)	117	138
Derivative liabilities (fair value)	780	86
Special Purpose Entities \| Credit-Linked Notes and Other \| Investment Grade
Variable Interest Entity
Retained interests (fair value)	0	57
Interests purchased in the secondary market (fair value)	2	423
Special Purpose Entities \| Credit-Linked Notes and Other \| Noninvestment Grade
Variable Interest Entity
Retained interests (fair value)	1,194	1,264
Interests purchased in the secondary market (fair value)	$ 31	$ 59

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+ References

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

-Publisher FASB

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