Fair Value Measurement and Election - Additional Information (Detail) (USD $)	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012	Dec. 31, 2012
Loans carried at fair value	$ 360,000,000	[1]		$ 379,000,000	[1]
Allowance for Loan and Lease Losses, Write-offs	(273,000,000)		(463,000,000)
Unfunded loan commitments and letters of credit	44,300,000,000			42,700,000,000
Allowance for unfunded loan commitments and letters of credit	56,000,000			49,000,000
Total Return Swap | Fair Value, Inputs, Level 2 [Member]
Loans carried at fair value	1,800,000,000			1,900,000,000
Interest Rate Lock Commitments
Transferred Out of Level 3 in The Fair Value Hierarchy	(135,000,000)		(172,000,000)
Collateralized Debt Obligations [Member] | Fair Value, Inputs, Level 2 [Member]
Debt Instrument, Fair Value Disclosure	286,000,000
Asset-backed Securities [Member] | Student Loans [Member]
Government guaranteed percent	97.00%
Trading Account Assets [Member] | Fair Value, Inputs, Level 2 [Member]
Trading loans were outstanding	373,000,000			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	0		(3,000,000)
Residential Mortgage, Loans Held For Sale [Member] | Nonperforming Financing Receivable [Member]
Transfer Of Portfolio Loans And Leases To Held For Sale Net Of Impairment	7,000,000		86,000,000
Allowance for Loan and Lease Losses, Write-offs	(1,000,000)		(26,000,000)
Loans sold at carrying value	17,000,000
Collateralized Loan Obligations [Member] | Fair Value, Inputs, Level 2 [Member]
Recognized losses due to changes in fair value attributable to borrower-specific credit risk	4,000,000		7,000,000
Brokered Deposits | Fair Value, Inputs, Level 2 [Member]
Recognized gains (losses) on liabilities due to changes in its own credit spread	(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	(21,000,000)		(9,000,000)
Fair Value, Measurements, Nonrecurring [Member] | Other Assets [Member] | Land [Member]
Asset Impairment Charges	0		0
Fair Value, Measurements, Nonrecurring [Member] | Other Assets [Member] | Property Subject to Operating Lease [Member]
Asset Impairment Charges	0		1,000,000
Fair Value, Measurements, Nonrecurring [Member] | Other Assets [Member] | Private Equity Partnership Investments [Member]
Asset Impairment Charges	0		0
Fair Value, Measurements, Nonrecurring [Member] | Affordable Housing [Member]
Asset Impairment Charges	0		0
Fair Value, Measurements, Recurring [Member]
Loans carried at fair value	360,000,000			379,000,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Loans carried at fair value	0			0
Debt Instrument, Fair Value Disclosure	1,632,000,000			1,622,000,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Loans carried at fair value	360,000,000			379,000,000
Debt Instrument, Fair Value Disclosure	$ 0			$ 0
Fair Value, Measurements, Recurring [Member] | Other real estate owned residential properties [Member] | Fair Value, Inputs, Level 3 [Member] | Lower Limit
Fair Value Inputs, Discount Rate, Variable Spread	25.00%
Fair Value, Measurements, Recurring [Member] | Other real estate owned residential properties [Member] | Fair Value, Inputs, Level 3 [Member] | Upper Limit
Fair Value Inputs, Discount Rate, Variable Spread	55.00%
Fair Value, Measurements, Recurring [Member] | Other real estate owned residential properties [Member] | Fair Value, Inputs, Level 3 [Member] | Weighted Average [Member]
Fair Value Inputs, Discount Rate, Variable Spread	36.00%
Fair Value, Measurements, Recurring [Member] | Other real estate owned commercial properties [Member] | Fair Value, Inputs, Level 3 [Member] | Lower Limit
Fair Value Inputs, Discount Rate, Variable Spread	15.00%
Fair Value, Measurements, Recurring [Member] | Other real estate owned commercial properties [Member] | Fair Value, Inputs, Level 3 [Member] | Upper Limit
Fair Value Inputs, Discount Rate, Variable Spread	45.00%
Fair Value, Measurements, Recurring [Member] | Other real estate owned commercial properties [Member] | Fair Value, Inputs, Level 3 [Member] | Weighted Average [Member]
Fair Value Inputs, Discount Rate, Variable Spread	35.00%

[1] 2 Includes loans of consolidated VIEs355 365