Variable Interest Entities - Loan Delinquencies and Net Charge-offs (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
Total assets held by securitization VIEs	$ 245,200		$ 245,200		$ 254,300
Mortgages - prime, including option ARMS
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
Total assets held by securitization VIEs	91,800		91,800		96,300
Mortgages - subprime
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
Total assets held by securitization VIEs	26,100		26,100		28,400
Mortgage-backed securities, Commercial
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
Total assets held by securitization VIEs	127,300		127,300		129,600
Securitized loans
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
90 days past due	17,550		17,550		19,358
Liquidation Losses	865	$ 1,470	1,780	$ 3,102
Securitized loans in which the firm has no continuing involvement	49,600		49,600		52,200
Securitized loans | Mortgages - prime, including option ARMS
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
90 days past due	10,036		10,036		11,363
Liquidation Losses	454	598	916	1,257
Securitized loans | Mortgages - subprime
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
90 days past due	6,045		6,045		6,473
Liquidation Losses	371	464	725	1,203
Securitized loans | Mortgage-backed securities, Commercial
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
90 days past due	1,469		1,469		1,522
Liquidation Losses	40	$ 408	139	$ 642
Variable Interest Entity, Not Primary Beneficiary
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
Securitized assets	193,676		193,676		198,391
Variable Interest Entity, Not Primary Beneficiary | Mortgages - prime, including option ARMS
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
Securitized assets	75,466		75,466		78,294
Variable Interest Entity, Not Primary Beneficiary | Mortgages - subprime
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
Securitized assets	24,237		24,237		25,659
Variable Interest Entity, Not Primary Beneficiary | Mortgage-backed securities, Commercial
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
Securitized assets	93,973		93,973		94,438
Variable Interest Entity, Primary Beneficiary
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
Assets held in consolidated securitization VIEs	1,900		1,900		3,700
Variable Interest Entity, Primary Beneficiary | Mortgages - prime, including option ARMS
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
Assets held in consolidated securitization VIEs	1,600		1,600		2,700
Variable Interest Entity, Primary Beneficiary | Mortgages - subprime
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
Assets held in consolidated securitization VIEs	100		100		800
Variable Interest Entity, Primary Beneficiary | Mortgage-backed securities, Commercial
Information about delinquencies, net charge-offs, and components of off-balance sheet securitized financial assets [Abstract]
Assets held in consolidated securitization VIEs	$ 200		$ 200		$ 200