Receivables Held for Sale - Summary of Components of Cumulative Lower of Amortized Cost or Fair Value Adjustment (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Lower of amortized cost or fair value adjustment recorded as a component of:
Lower of amortized cost or fair value adjustment	$ 748		$ 18
Real Estate Owned [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Lower of amortized cost or fair value adjustment	(40)		(50)
Short Sales [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Lower of amortized cost or fair value adjustment	(22)		(20)
Provision for Loan and Lease Losses [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Provision for credit losses			112
Provision for Loan and Lease Losses [Member] | Fair Value [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Provision for credit losses			112
Provision for Loan and Lease Losses [Member] | Real Estate Owned [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Provision for credit losses			0
Provision for Loan and Lease Losses [Member] | Short Sales [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Provision for credit losses			0
Other Income [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Initial lower of amortized cost or fair value adjustment	212		1,547
Subsequent to initial transfer to held for sale	(748)	[1]	(18)
Total recorded through other revenues	(536)		1,529
Lower of amortized cost or fair value adjustment	(536)		1,641
Other Income [Member] | Fair Value [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Initial lower of amortized cost or fair value adjustment	212		1,547
Subsequent to initial transfer to held for sale	(686)	[1]	52
Total recorded through other revenues	(474)		1,599
Lower of amortized cost or fair value adjustment	(474)		1,711
Other Income [Member] | Real Estate Owned [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Initial lower of amortized cost or fair value adjustment	0		0
Subsequent to initial transfer to held for sale	(40)	[1]	(50)
Total recorded through other revenues	(40)		(50)
Lower of amortized cost or fair value adjustment	(40)		(50)
Other Income [Member] | Short Sales [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Initial lower of amortized cost or fair value adjustment	0		0
Subsequent to initial transfer to held for sale	(22)	[1]	(20)
Total recorded through other revenues	(22)		(20)
Lower of amortized cost or fair value adjustment	$ (22)		$ (20)

[1] For 2013, the fair value of the lower of amortized cost or fair value adjustment reflects an increase in the relative fair value of $768 million related to real estate secured receivables held for sale and an additional charge of $82 million related to personal non-credit card receivables prior to the sale of this portfolio on April 1, 2013.