Portfolio Balances and Delinquency Balances Based on 90 days or more Past Due and Net Charge-Offs Related to Managed Portfolio Loans (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013	Dec. 31, 2013
Cash Flows Between Transferor and Transferee, Receipts on Transferor's Interest in Transferred Financial Assets, Other	$ 2		$ 8	$ 14		$ 26
Principal Amount Outstanding on Loans Managed and Securitized or Asset-backed Financing Arrangement	235,826	[1]		235,826	[1]		230,189	[1]
Past Due	2,132	[2]		2,132	[2]		2,721	[2]
Net Credit Losses During Period on Loans Managed or Securitized or Asset-backed Financing Arrangement	134		151	364		570
Loans
Principal Balance	132,151	[1]		132,151	[1]		127,877	[1]
Past Due	1,828	[2]		1,828	[2]		2,199	[2]
Net Credit Losses During Period on Loans Managed or Securitized or Asset-backed Financing Arrangement	128		146	351		551
Commercial Portfolio Segment [Member] | Loans
Principal Balance	71,094	[1]		71,094	[1]		64,310	[1]
Past Due	232	[2]		232	[2]		272	[2]
Net Credit Losses During Period on Loans Managed or Securitized or Asset-backed Financing Arrangement	12		39	57		128
Commercial Portfolio Segment [Member] | Managed Securitized Loans
Past Due	0	[2]		0	[2]		29	[2]
Net Credit Losses During Period on Loans Managed or Securitized or Asset-backed Financing Arrangement	0		0	0		0
Continuing Involvement with Derecognized Transferred Financial Assets, Amount Outstanding	0	[1]		0	[1]		1,617	[1]
Residential Portfolio Segment [Member] | Loans
Principal Balance	39,222	[1]		39,222	[1]		43,190	[1]
Past Due	968	[2]		968	[2]		1,296	[2]
Net Credit Losses During Period on Loans Managed or Securitized or Asset-backed Financing Arrangement	92		88	227		363
Residential Portfolio Segment [Member] | Managed Securitized Loans
Past Due	304	[2],[3]		304	[2],[3]		493	[2],[3]
Net Credit Losses During Period on Loans Managed or Securitized or Asset-backed Financing Arrangement	6		5	13		19
Continuing Involvement with Derecognized Transferred Financial Assets, Amount Outstanding	103,675	[1]		103,675	[1]		100,695	[1]
Consumer Portfolio Segment [Member] | Loans
Principal Balance	21,835	[1]		21,835	[1]		20,377	[1]
Past Due	628	[2]		628	[2]		631	[2]
Net Credit Losses During Period on Loans Managed or Securitized or Asset-backed Financing Arrangement	24		19	67		60
Residential Mortgage [Member]
Cash Flows Between Transferor and Transferee, Receipts on Transferor's Interest in Transferred Financial Assets, Other	$ 2		$ 8	$ 13	[4],[5]	$ 24

[1] Excludes $1.7 billion of LHFS at both September 30, 2014 and December 31, 2013.

[2] Excludes $53 million and $17 million of past due LHFS at September 30, 2014 and December 31, 2013, respectively.

[3] Excludes loans that have completed the foreclosure or short sale process (i.e. involuntary prepayments)

[4] The transfer activity is related to unconsolidated VIEs.

[5] Does not include GSE mortgage loan transfers