LHFI by Credit Quality Indicator (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012		Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 122,691	[1]	$ 122,495	[1]
Commercial and Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	50,189		49,538
Commercial and Industrial | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	48,213		47,683
Commercial and Industrial | Criticized Accruing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,639		1,507
Commercial and Industrial | Criticized Nonaccruing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	337		348
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	4,910		5,094
Commercial Real Estate | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,754		3,845
Commercial Real Estate | Criticized Accruing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	876		961
Commercial Real Estate | Criticized Nonaccruing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	280		288
Commercial Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,086		1,240
Commercial Construction | Pass
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	568		581
Commercial Construction | Criticized Accruing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	320		369
Commercial Construction | Criticized Nonaccruing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	198		290
Residential Nonguaranteed
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	23,653	[2]	23,243	[2]
Residential Nonguaranteed | FICO Score 700 and Above
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	16,533	[2]	16,139	[2]
Residential Nonguaranteed | FICO Score Between 620 and 699
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	4,212	[2]	4,132	[2]
Residential Nonguaranteed | FICO Score Below 620
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,908	[2],[3]	2,972	[2],[3]
Home Equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	15,472		15,765
Home Equity | FICO Score 700 and Above
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	11,630		11,084
Home Equity | FICO Score Between 620 and 699
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	2,443		2,903
Home Equity | FICO Score Below 620
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,399	[3]	1,778	[3]
Residential Construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	924		980
Residential Construction | FICO Score 700 and Above
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	616		661
Residential Construction | FICO Score Between 620 and 699
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	198		202
Residential Construction | FICO Score Below 620
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	110	[3]	117	[3]
Consumer Other Direct
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,688	[4]	1,610	[4]
Consumer Other Direct | FICO Score 700 and Above
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,383	[4]	1,251	[4]
Consumer Other Direct | FICO Score Between 620 and 699
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	228	[4]	273	[4]
Consumer Other Direct | FICO Score Below 620
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	77	[3],[4]	86	[3],[4]
Consumer Indirect
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	10,145		10,165
Consumer Indirect | FICO Score 700 and Above
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	7,634		7,397
Consumer Indirect | FICO Score Between 620 and 699
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	1,826		1,990
Consumer Indirect | FICO Score Below 620
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	685	[3]	778	[3]
Consumer Credit Card
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	527		540
Consumer Credit Card | FICO Score 700 and Above
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	337		347
Consumer Credit Card | FICO Score Between 620 and 699
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	138		142
Consumer Credit Card | FICO Score Below 620
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 52	[3]	$ 51	[3]

[1] Includes loans of consolidated VIEs1,378 3,322

[2] Excludes $6.4 billion and $6.7 billion at March 31, 2012 and December 31, 2011, respectively, of guaranteed residential loans. At both March 31, 2012 and December 31, 2011, the majority of these loans had FICO scores of 700 and above.

[3] For substantially all loans with refreshed FICO scores below 620, the borrower’s FICO score at the time of origination exceeded 620 but has since deteriorated as the loan has seasoned.

[4] Excludes $464 million and $449 million as of March 31, 2012 and December 31, 2011, respectively, of private-label student loans with third party insurance. At March 31, 2012 and December 31, 2011, the majority of these loans had FICO scores of 700 and above.