Off-Balance Sheet Lending-Related Financial Instruments, Guarantees and Other Commitments (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	$ 935,582		$ 950,997	$ 1,041,373
Off-balance sheet lending-related financial commitments, carrying value	1,094		1,176
Allowance for lending-related commitments	231	$ 252	275	436	$ 564	$ 681
Off balance sheet lending related financial instruments guarantees and other commitments - supplemental information [Abstract]
Standby letters of credit, unissued commitments	44,900		45,600
Unfunded commitments investments private equity funds third party	140		147
Unfunded commitments investments other equity investments	1,100		961
Investments entities that calculate net asset value per share, unfunded commitments	155		150
Commitments to extend credit leveraged and acquisition finance activities	29,300		23,400
Maximum
Off balance sheet lending related financial instruments guarantees and other commitments - supplemental information [Abstract]
Secured clearance advance facility outstanding commitment	11,300		12,600
Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	642,639
Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	128,719
Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	145,474
Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	18,750
Wholesale
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	$ 352,048			$ 451,275
Lending-Related Commitments | Days Past Due, 60 or More | Credit Card
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Line of credit close criteria, period past due	60 days
Consumer Loan
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	$ 583,534		584,116
Off-balance sheet lending-related financial commitments, carrying value	15		13
Consumer Loan | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	560,593
Consumer Loan | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	11,859
Consumer Loan | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	2,335
Consumer Loan | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	8,747
Consumer loan excluding credit card
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	59,817		58,153
Off-balance sheet lending-related financial commitments, carrying value	15		13
Consumer loan excluding credit card | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	36,876
Consumer loan excluding credit card | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	11,859
Consumer loan excluding credit card | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	2,335
Consumer loan excluding credit card | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	8,747
Home equity - senior lien
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	11,085		11,807
Off-balance sheet lending-related financial commitments, carrying value	0		0
Home equity - senior lien | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	1,826
Home equity - senior lien | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	4,364
Home equity - senior lien | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	996
Home equity - senior lien | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	3,899
Home equity - junior lien
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	13,158		14,859
Off-balance sheet lending-related financial commitments, carrying value	0		0
Home equity - junior lien | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	2,927
Home equity - junior lien | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	5,291
Home equity - junior lien | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	1,039
Home equity - junior lien | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	3,901
Prime mortgage
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	13,526		8,579
Off-balance sheet lending-related financial commitments, carrying value	0		0
Prime mortgage | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	13,526
Prime mortgage | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	0
Prime mortgage | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	0
Prime mortgage | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	0
Auto
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	9,255		10,462
Off-balance sheet lending-related financial commitments, carrying value	3		2
Auto | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	7,647
Auto | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	1,365
Auto | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	211
Auto | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	32
Business banking
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	12,316		11,894
Off-balance sheet lending-related financial commitments, carrying value	12		11
Business banking | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	10,923
Business banking | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	834
Business banking | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	89
Business banking | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	470
Student and other
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	477		552
Off-balance sheet lending-related financial commitments, carrying value	0		0
Student and other | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	27
Student and other | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	5
Student and other | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	0
Student and other | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	445
Credit Card
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	523,717		525,963
Off-balance sheet lending-related financial commitments, carrying value	0		0
Credit Card | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	523,717
Credit Card | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	0
Credit Card | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	0
Credit Card | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	0
Commercial loan
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	352,048		366,881
Off-balance sheet lending-related financial commitments, carrying value	1,079		$ 1,163
Commercial loan | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	82,046
Commercial loan | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	116,860
Commercial loan | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	143,139
Commercial loan | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	$ 10,003
Commercial loan | Wholesale | Total U.S.
Off balance sheet lending related financial instruments guarantees and other commitments - supplemental information [Abstract]
Off balance sheet lending related financial commitments, percent	76.00%		73.00%
Other unfunded commitments to extend credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	$ 262,436		$ 272,676
Off-balance sheet lending-related financial commitments, carrying value	327		374
Off balance sheet lending related financial instruments guarantees and other commitments - supplemental information [Abstract]
Off balance sheet lending related commitments wholesale contractual amount net of risk participations other unfunded commitments to extend credit	239		243
Credit enhancements and bond and commercial paper liquidity commitments to US states and municipalities hospitals and other not for profit entities	14,000		14,800
Other unfunded commitments to extend credit | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	58,701
Other unfunded commitments to extend credit | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	85,922
Other unfunded commitments to extend credit | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	110,091
Other unfunded commitments to extend credit | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	7,722
Standby letters of credit and other financial guarantees
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	85,424		89,874
Off-balance sheet lending-related financial commitments, carrying value	751		788
Allowance for lending-related commitments	277		234
Off balance sheet lending related financial instruments guarantees and other commitments - supplemental information [Abstract]
Off balance sheet Lending related commitments Wholesale Contractual amount Net of Risk Participations Standby letters of credit and other financial guarantees	12,500		13,000
Credit enhancements and bond and commercial paper liquidity commitments to US states and municipalities hospitals and other not for profit entities	10,800		13,300
Standby letters of credit and other financial guarantees | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	20,104
Standby letters of credit and other financial guarantees | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	30,071
Standby letters of credit and other financial guarantees | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	32,968
Standby letters of credit and other financial guarantees | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	2,281
Other letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	4,188		4,331
Off-balance sheet lending-related financial commitments, carrying value	1		1
Allowance for lending-related commitments	1		1
Off balance sheet lending related financial instruments guarantees and other commitments - supplemental information [Abstract]
Off balance sheet Lending related commitments Wholesale Contractual amount Net of Risk Participations Other letters of credit	376		469
Other letters of credit | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	3,241
Other letters of credit | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	867
Other letters of credit | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	80
Other letters of credit | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Off-balance sheet lending-related financial commitments, contractual amount	0
Securities lending indemnification agreements and guarantees
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	190,441		171,059
Guarantor obligations, current carrying value	0		0
Off balance sheet lending related financial instruments guarantees and other commitments - supplemental information [Abstract]
Indemnification agreement securities lending guarantees collateral held in support of	197,600		177,100
Securities lending indemnification agreements and guarantees | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	190,441
Securities lending indemnification agreements and guarantees | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	0
Securities lending indemnification agreements and guarantees | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	0
Securities lending indemnification agreements and guarantees | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	0
Derivatives qualifying as guarantees
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	51,476		53,589
Guarantor obligations, current carrying value	103		80
Derivatives qualifying as guarantees | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	930
Derivatives qualifying as guarantees | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	293
Derivatives qualifying as guarantees | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	11,459
Derivatives qualifying as guarantees | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	38,794
Unsettled reverse repurchase and securities borrowing agreements
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	49,684		40,993
Guarantor obligations, current carrying value	0		0
Unsettled reverse repurchase and securities borrowing agreements | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	49,684
Unsettled reverse repurchase and securities borrowing agreements | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	0
Unsettled reverse repurchase and securities borrowing agreements | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	0
Unsettled reverse repurchase and securities borrowing agreements | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	0
Mortgage repurchase liability | Warranty Reserves
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Allowance for lending-related commitments	231		275
Loans sold with recourse
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Indemnification agreements loan sale and securitization loans sold with recourse contractual amount	5,173		6,063
Indemnification agreements, loan sale and securitization, loans sold with recourse: carrying value	92		102
Other guarantees and commitments
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	5,984		5,720
Guarantor obligations, current carrying value	(107)		(121)
Other guarantees and commitments | Expires in one year or less
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	797
Other guarantees and commitments | Expires after one year through three years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	1,635
Other guarantees and commitments | Expires after three years through five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	2,259
Other guarantees and commitments | Expires after five years
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	1,293
Letters of credit hedged by derivative transactions
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Other guarantees and commitments, contractual amount	$ 4,400		$ 4,500