Fair Value Measurement and Election - Additional Information (Detail) (USD $)	3 Months Ended			6 Months Ended			12 Months Ended
	Jun. 30, 2013		Jun. 30, 2012	Jun. 30, 2013		Jun. 30, 2012	Dec. 31, 2012
Transfer of Loans Held-for-sale to Portfolio Loans	$ 5,000,000		$ 20,000,000	$ 17,000,000		$ 31,000,000
Loans Receivable, Fair Value Disclosure	339,000,000	[1]		339,000,000	[1]		379,000,000	[1]
Allowance for Loan and Lease Losses, Write-offs	(233,000,000)		(397,000,000)	(506,000,000)		(860,000,000)
Gain (Loss) on Sales of Loans, Net	3,000,000		30,000,000	7,000,000		36,000,000
Unfunded loan commitments and letters of credit	44,900,000,000			44,900,000,000			42,700,000,000
Allowance for unfunded loan commitments and letters of credit	50,000,000			50,000,000			49,000,000
Total Return Swap | Fair Value, Inputs, Level 2 [Member]
Loans Receivable, Fair Value Disclosure	1,800,000,000			1,800,000,000			1,900,000,000
Interest Rate Lock Commitments
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	74,000,000		218,000,000	209,000,000		390,000,000
Asset-backed Securities [Member] | Student Loans [Member]
Government guaranteed percent	97.00%			97.00%
Trading Account Assets [Member] | Commercial and Corporate Leveraged Loans [Member] | Fair Value, Inputs, Level 2 [Member]
Loans Receivable, Fair Value Disclosure	418,000,000			418,000,000			357,000,000
Residential Mortgage, Loans Held For Sale [Member] | Fair Value, Inputs, Level 2 [Member]
Recognized losses due to changes in fair value attributable to borrower-specific credit risk	(2,000,000)		5,000,000	(2,000,000)		2,000,000
Collateralized Loan Obligations [Member] | Fair Value, Inputs, Level 2 [Member]
Recognized losses due to changes in fair value attributable to borrower-specific credit risk	(1,000,000)		(2,000,000)	3,000,000		5,000,000
Brokered Deposits [Member] | Fair Value, Inputs, Level 2 [Member]
Recognized gains (losses) on liabilities due to changes in its own credit spread	0		(1,000,000)	(1,000,000)		(6,000,000)
Long-term Debt [Member] | Fair Value, Inputs, Level 2 [Member]
Recognized gains (losses) on liabilities due to changes in its own credit spread	(1,000,000)		1,000,000	(19,000,000)		(8,000,000)
Loans Held-for-Sale | Nonperforming Financing Receivable [Member]
Transfer Of Portfolio Loans And Leases To Held For Sale Net Of Impairment				22,000,000		116,000,000
Loans Held-for-Sale | Residential Portfolio Segment [Member]
Loans sold at carrying value				39,000,000
Gain (Loss) on Sales of Loans, Net				5,000,000
Loans Held-for-Sale | Nonperforming Residential Mortgages Transferred To Held For Sale During Period [Member]
Transfer of Loans Held-for-sale to Portfolio Loans						7,000,000
Allowance for Loan and Lease Losses, Write-offs				(3,000,000)		(35,000,000)
Loans sold at carrying value						71,000,000
Gain (Loss) on Sale of Loans and Leases						4,000,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Loans Receivable, Fair Value Disclosure	0			0			0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Loans Receivable, Fair Value Disclosure	339,000,000			339,000,000			379,000,000
Collateralized Debt Obligations [Member] | Fair Value, Inputs, Level 2 [Member]
Debt Instrument, Fair Value Disclosure	285,000,000			285,000,000
Other real estate owned residential properties [Member] | Fair Value, Measurements, Nonrecurring [Member] | Lower Limit | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Discount Rate, Variable Spread				30.00%
Other real estate owned residential properties [Member] | Fair Value, Measurements, Nonrecurring [Member] | Upper Limit | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Discount Rate, Variable Spread				60.00%
Other real estate owned residential properties [Member] | Fair Value, Measurements, Nonrecurring [Member] | Weighted Average [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Discount Rate, Variable Spread				44.00%
Other Assets [Member] | Fair Value, Measurements, Nonrecurring [Member]
Asset Impairment Charges	3,000,000			4,000,000			13,000,000
Other Assets [Member] | Fair Value, Measurements, Nonrecurring [Member] | Repossessed Personal Property [Member]
Asset Impairment Charges			0	3,000,000		1,000,000
Other Assets [Member] | Fair Value, Measurements, Nonrecurring [Member] | Land [Member]
Asset Impairment Charges	0		0	0		0
Other Assets [Member] | Fair Value, Measurements, Nonrecurring [Member] | Property Subject to Operating Lease [Member]
Asset Impairment Charges	0		0	1,000,000		1,000,000
Other Assets [Member] | Fair Value, Measurements, Nonrecurring [Member] | Private Equity Partnership Investments [Member]
Asset Impairment Charges	0		0	0		0
Affordable Housing [Member] | Fair Value, Measurements, Nonrecurring [Member]
Asset Impairment Charges	$ 2,000,000		$ 0	$ 2,000,000		$ 0	$ 96,000,000
Other real estate owned commercial properties [Member] | Fair Value, Measurements, Nonrecurring [Member] | Lower Limit | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Discount Rate, Variable Spread				15.00%
Other real estate owned commercial properties [Member] | Fair Value, Measurements, Nonrecurring [Member] | Upper Limit | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Discount Rate, Variable Spread				45.00%
Other real estate owned commercial properties [Member] | Fair Value, Measurements, Nonrecurring [Member] | Weighted Average [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Discount Rate, Variable Spread				36.00%

[1] 2 Includes loans of consolidated VIEs345 365