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, 2012
Lower of amortized cost or fair value adjustment recorded as a component of:
Provision for credit losses	$ 112	[1]
Other revenues:
Initial lower of amortized cost or fair value adjustment	1,547	[2]
Subsequent to initial transfer to held for sale	(18)	[3]
Total recorded through other revenues	1,529
Lower of amortized cost or fair value adjustment	1,641
Fair Value [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Provision for credit losses	112	[1]
Other revenues:
Initial lower of amortized cost or fair value adjustment	1,547	[2]
Subsequent to initial transfer to held for sale	52	[3]
Total recorded through other revenues	1,599
Lower of amortized cost or fair value adjustment	1,711
REO [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Provision for credit losses	0	[1]
Other revenues:
Initial lower of amortized cost or fair value adjustment	0	[2]
Subsequent to initial transfer to held for sale	(50)	[3]
Total recorded through other revenues	(50)
Lower of amortized cost or fair value adjustment	(50)
Short Sales [Member]
Lower of amortized cost or fair value adjustment recorded as a component of:
Provision for credit losses	0	[1]
Other revenues:
Initial lower of amortized cost or fair value adjustment	0	[2]
Subsequent to initial transfer to held for sale	(20)	[3]
Total recorded through other revenues	(20)
Lower of amortized cost or fair value adjustment	$ (20)

[1] The portion of the initial lower of amortized cost or fair value adjustment attributable to credit for personal non-credit card receivables which was recorded as a provision for credit losses in the consolidated statement of income (loss). This was determined by giving consideration to the impact of over-the-life credit loss estimates as compared to the existing credit loss reserves prior to our decision to transfer to receivables held for sale. There was no lower of cost or fair value adjustment allocated to credit for the real estate secured receivables as these receivables were previously carried at the lower of amortized cost or fair value of the collateral less cost to sell prior to the transfer of the loans to held for sale.

[2] The portion of the lower of amortized cost or fair value adjustment which reflects the impact on value caused by current marketplace conditions including changes in interest rates and illiquidity and is recorded as a component of total other revenues in the consolidated statement of income (loss).

[3] The additional lower of amortized cost or fair value adjustments subsequent to the transfer to receivable held for sale associated with fair value reflects the change in the fair value of the receivables held for sale, net of reversals associated with liquidations other than REO and short sales.