Loans and Allowance for Credit Losses, Loans by Delinquency Status, Consumer (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014		Dec. 31, 2013		Dec. 31, 2008
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired Loans (carrying value)	$ 24,236		$ 26,727		$ 58,797
Loans	838,883	[1],[2]	822,286	[1],[2]
Total Consumer [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired Loans (carrying value)	22,377		24,223		40,093
Loans	442,400		445,043
Real estate 1-4 family first mortgage [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired Loans (carrying value)	22,271		24,100		39,214
Loans	263,326		258,497
Real estate 1-4 family junior lien mortgage [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired Loans (carrying value)	106		123		728
Loans	60,844		65,914
Credit Card [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired Loans (carrying value)	0		0
Loans	28,270		26,870
Automobile [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired Loans (carrying value)	0		0		151
Loans	55,242		50,808
Other revolving credit and installment [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Purchased Credit Impaired Loans (carrying value)	0		0
Loans	34,718		42,954
Loans Excluding Purchased Credit-Impaired Loans [Member] | Total Consumer [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current-29 DPD	381,269		365,323
30-59 DPD	4,123		4,477
60-89 DPD	1,774		1,851
90-119 DPD	980		1,035
120-179 DPD	1,027		1,183
180+ DPD	4,908		5,518
Government insured/guaranteed loans	25,942		41,433
Loans, excluding Purchased Credit Impaired Loans	420,023		420,820
Loans Excluding Purchased Credit-Impaired Loans [Member] | Real estate 1-4 family first mortgage [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current-29 DPD	205,905		193,361
30-59 DPD	2,505		2,784
60-89 DPD	1,088		1,157
90-119 DPD	557		587
120-179 DPD	627		747
180+ DPD	4,431		5,024
Government insured/guaranteed loans	25,942		30,737
Loans, excluding Purchased Credit Impaired Loans	241,055		234,397
Loans Excluding Purchased Credit-Impaired Loans [Member] | Real estate 1-4 family junior lien mortgage [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current-29 DPD	59,293		64,194
30-59 DPD	400		461
60-89 DPD	230		253
90-119 DPD	160		182
120-179 DPD	192		216
180+ DPD	463		485
Government insured/guaranteed loans	0		0
Loans, excluding Purchased Credit Impaired Loans	60,738		65,791
Loans Excluding Purchased Credit-Impaired Loans [Member] | Credit Card [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current-29 DPD	27,619		26,203
30-59 DPD	206		202
60-89 DPD	143		144
90-119 DPD	118		124
120-179 DPD	183		196
180+ DPD	1		1
Government insured/guaranteed loans	0		0
Loans, excluding Purchased Credit Impaired Loans	28,270		26,870
Loans Excluding Purchased Credit-Impaired Loans [Member] | Automobile [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current-29 DPD	54,105		49,699
30-59 DPD	856		852
60-89 DPD	204		186
90-119 DPD	70		66
120-179 DPD	6		4
180+ DPD	1		1
Government insured/guaranteed loans	0		0
Loans, excluding Purchased Credit Impaired Loans	55,242		50,808
Loans Excluding Purchased Credit-Impaired Loans [Member] | Other revolving credit and installment [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current-29 DPD	34,347		31,866
30-59 DPD	156		178
60-89 DPD	109		111
90-119 DPD	75		76
120-179 DPD	19		20
180+ DPD	12		7
Government insured/guaranteed loans	0		10,696
Loans, excluding Purchased Credit Impaired Loans	$ 34,718		$ 42,954

[1] Parenthetical amounts represent assets and liabilities for which we have elected the fair value option.

[2] Financial information for certain periods prior to 2014 was revised to reflect our determination that certain factoring arrangements did not qualify as loans. See Note 1 for more information.