LHFI by Credit Quality Indicator (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	$ 129,196	[1]	$ 127,877	[1]
Loans and Leases Receivable, Impaired, Commitment to Lend	8		8
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	42,795		43,190
Residential Guaranteed [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,295		3,416
Residential Nonguaranteed [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	24,331	[2],[3]	24,412	[2],[4]
Federally Guaranteed Student Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	5,533		5,545
FICO Score 700 and Above [Member] | Residential Guaranteed [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,300		3,400
FICO Score 700 and Above [Member] | Residential Nonguaranteed [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	18,983	[2]	19,100	[2]
Loans Held For Investment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	129,196		127,877
Loans Held For Investment [Member] | Residential Guaranteed [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	3,295		3,416
Loans Held For Investment [Member] | Residential Nonguaranteed [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	24,331	[5]	24,412	[5]
Loans Held For Investment [Member] | Federally Guaranteed Student Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	5,533		5,545
Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Government guaranteed percent	8.00%		8.00%
Credit Concentration Risk [Member] | Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for investment	42,800		43,200
ResidentialLoansInterestOnlyHighOriginalLTVAndOrSecondLien	12,200		12,400
Residential Mortgage Interest Only Loans [Member] | Credit Concentration Risk [Member] | Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
ResidentialLoansInterestOnlyHighOriginalLTVAndOrSecondLien	5,200		5,500
LoansWithNoMortgageInsuranceAndFirstLienHighOriginalLTVOrSecondLien [Member] | Residential Mortgage Interest Only Loans [Member] | Credit Concentration Risk [Member] | Residential Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
ResidentialLoansInterestOnlyHighOriginalLTVAndOrSecondLien	$ 1,073		$ 1,100

[1] Includes loans of consolidated VIEs of $318 million and $327 million at March 31, 2014 and December 31, 2013, respectively.

[2] Excludes $3.3 billion and $3.4 billion at March 31, 2014 and December 31, 2013, respectively, of guaranteed residential loans. At March 31, 2014 and December 31, 2013, the majority of these loans had FICO scores of 700 and above.

[3] Includes $299 million of loans carried at fair value, the majority of which were accruing current.

[4] Includes $302 million of loans carried at fair value, the majority of which were accruing current.

[5] Includes $299 million and $302 million of loans carried at fair value at March 31, 2014 and December 31, 2013, respectively.