Allowances for Loan and Lease Losses and Unfunded Loan Commitments and Letters of Credit (Rollforward of Allowance For Loan and Lease Losses and Associated Loan Data) (Details) - USD ($)		3 Months Ended			6 Months Ended
		Jun. 30, 2015		Jun. 30, 2014	Jun. 30, 2015		Jun. 30, 2014	Dec. 31, 2014
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance					$ 3,331,000,000	[1]	$ 3,609,000,000
Charge-offs					(392,000,000)		(564,000,000)
Recoveries					222,000,000		233,000,000
Net charge-offs					(170,000,000)		(331,000,000)
Provision For Credit Losses		$ 46,000,000		$ 72,000,000	100,000,000		166,000,000
Net change in allowance for unfunded loan commitments and letters of credit					13,000,000		10,000,000
Other					(2,000,000)		(1,000,000)
Ending Balance	[1]	3,272,000,000		3,453,000,000	3,272,000,000		3,453,000,000
TDRs individually evaluated for impairment - associated allowance		309,000,000		436,000,000	309,000,000		436,000,000	$ 386,000,000
Other loans individually evaluated for impairment - associated allowance		65,000,000		118,000,000	65,000,000		118,000,000
Loans collectively evaluated for impairment - associated allowance		2,043,000,000		2,013,000,000	2,043,000,000		2,013,000,000
Purchased impaired loans - associated allowance		855,000,000		886,000,000	855,000,000		886,000,000
TDRs individually evaluated for impairment		2,416,000,000		2,666,000,000	2,416,000,000		2,666,000,000
Other loans individually evaluated for impairment		282,000,000		526,000,000	282,000,000		526,000,000
Loans collectively evaluated for impairment		197,049,000,000		191,250,000,000	197,049,000,000		191,250,000,000
Fair value option loans		941,000,000		985,000,000	941,000,000		985,000,000
Purchased impaired loans		4,465,000,000		5,557,000,000	4,465,000,000		5,557,000,000	4,858,000,000
Total loans		$ 205,153,000,000	[1],[2]	$ 200,984,000,000	$ 205,153,000,000	[1],[2]	$ 200,984,000,000	204,817,000,000	[1],[2]
Portfolio segment ALLL as a percentage of total ALLL		100.00%		100.00%	100.00%		100.00%
Ratio of the allowance for loan and lease losses to total loans		1.59%		1.72%	1.59%		1.72%
Evaluated for impairment based upon collateral values
Financing Receivable Allowance For Credit Losses [Line Items]
Loans collectively evaluated for impairment		$ 174,000,000		$ 232,000,000	$ 174,000,000		$ 232,000,000
Total commercial lending [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance					1,571,000,000		1,547,000,000
Charge-offs					(108,000,000)		(209,000,000)
Recoveries					134,000,000		149,000,000
Net charge-offs					26,000,000		(60,000,000)
Provision For Credit Losses					20,000,000		108,000,000
Net change in allowance for unfunded loan commitments and letters of credit					13,000,000		10,000,000
Other					(2,000,000)		(1,000,000)
Ending Balance		1,628,000,000		1,604,000,000	1,628,000,000		1,604,000,000
TDRs individually evaluated for impairment - associated allowance		35,000,000		29,000,000	35,000,000		29,000,000
Other loans individually evaluated for impairment - associated allowance		65,000,000		118,000,000	65,000,000		118,000,000
Loans collectively evaluated for impairment - associated allowance		1,461,000,000		1,349,000,000	1,461,000,000		1,349,000,000
Purchased impaired loans - associated allowance		67,000,000		108,000,000	67,000,000		108,000,000
TDRs individually evaluated for impairment		414,000,000		545,000,000	414,000,000		545,000,000
Other loans individually evaluated for impairment		282,000,000		526,000,000	282,000,000		526,000,000
Loans collectively evaluated for impairment		129,791,000,000		122,533,000,000	129,791,000,000		122,533,000,000
Purchased impaired loans		235,000,000		479,000,000	235,000,000		479,000,000	310,000,000
Total loans		$ 130,722,000,000		$ 124,083,000,000	$ 130,722,000,000		$ 124,083,000,000	128,368,000,000
Portfolio segment ALLL as a percentage of total ALLL		50.00%		46.00%	50.00%		46.00%
Ratio of the allowance for loan and lease losses to total loans		1.25%		1.29%	1.25%		1.29%
Total consumer lending [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance					$ 1,760,000,000		$ 2,062,000,000
Charge-offs					(284,000,000)		(355,000,000)
Recoveries					88,000,000		84,000,000
Net charge-offs					(196,000,000)		(271,000,000)
Provision For Credit Losses					80,000,000		58,000,000
Ending Balance		$ 1,644,000,000		$ 1,849,000,000	1,644,000,000		1,849,000,000
TDRs individually evaluated for impairment - associated allowance		274,000,000		407,000,000	274,000,000		407,000,000
Loans collectively evaluated for impairment - associated allowance		582,000,000		664,000,000	582,000,000		664,000,000
Purchased impaired loans - associated allowance		788,000,000		778,000,000	788,000,000		778,000,000
TDRs individually evaluated for impairment		2,002,000,000		2,121,000,000	2,002,000,000		2,121,000,000
Loans collectively evaluated for impairment		67,258,000,000		68,717,000,000	67,258,000,000		68,717,000,000
Fair value option loans		941,000,000		985,000,000	941,000,000		985,000,000
Purchased impaired loans		4,230,000,000		5,078,000,000	4,230,000,000		5,078,000,000	4,548,000,000
Total loans		$ 74,431,000,000		$ 76,901,000,000	$ 74,431,000,000		$ 76,901,000,000	$ 76,449,000,000
Portfolio segment ALLL as a percentage of total ALLL		50.00%		54.00%	50.00%		54.00%
Ratio of the allowance for loan and lease losses to total loans		2.21%		2.40%	2.21%		2.40%
Total consumer lending [Member] | Quantifying Misstatement In Financial Statments - End of Period Impact
Financing Receivable Allowance For Credit Losses [Line Items]
Loans collectively evaluated for impairment				$ (101,000,000)			$ (101,000,000)
Fair value option loans				$ 101,000,000			$ 101,000,000

[1] Amounts represent the assets or liabilities of consolidated variable interest entities (VIEs).

[2] Amounts represent items for which we have elected the fair value option.