Business Segments - Reconciliation of IFRS Basis Segment Results (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012
Operating Statistics [Line Items]
US GAAP based Net interest income	$ 238		$ 391		$ 632		$ 799
US GAAP based Other operating income (Total other revenues)	628		(1,865)		982		(2,060)
US GAAP based Total operating income (loss)	866		(1,474)		1,614		(1,261)
US GAAP based Loan impairment charges (Provision for credit losses)	267	[1]	738	[1],[2]	291	[1]	1,529	[1],[2]
US GAAP Net interest income and other operating income less provision for credit losses	599		(2,212)		1,323		(2,790)
US GAAP based Operating expenses	195		239		463		454
Income (loss) from continuing operations before income tax	404		(2,451)		860		(3,244)
Customer loans (Receivables)	29,112		34,955		29,112		34,955
US GAAP based Assets	41,872		49,292		41,872		49,292
IFRS Basis Consolidated Totals
Operating Statistics [Line Items]
IFRS based Net interest income	493		622		1,129		1,267
IFRS based Other operating income (Total other revenues)	(116)		(431)		(315)		(748)
IFRS based Total operating income (loss)	377		191		814		519
IFRS based Loan impairment charges (Provision for credit losses)	124		720		443		1,575
IFRS based Net interest income and other operating income less provision for credit losses	253		(529)		371		(1,056)
IFRS based Operating expense	153		221		408		410
IFRS based Profit (loss) before tax	100		(750)		(37)		(1,466)
IFRS based Customer loans (Receivables)	34,498		44,437		34,498		44,437
IFRS based Assets	43,839		52,696		43,839		52,696
IFRS Adjustments
Operating Statistics [Line Items]
IFRS based Net interest income	(168)	[3]	(127)	[3]	(327)	[3]	(249)	[3]
IFRS based Other operating income (Total other revenues)	658	[3]	(1,550)	[3]	1,120	[3]	(1,563)	[3]
IFRS based Total operating income (loss)	490	[3]	(1,677)	[3]	793	[3]	(1,812)	[3]
IFRS based Loan impairment charges (Provision for credit losses)	143	[3]	18	[3]	(152)	[3]	(46)	[3]
IFRS based Net interest income and other operating income less provision for credit losses	347	[3]	(1,695)	[3]	945	[3]	(1,766)	[3]
IFRS based Operating expense	43	[3]	6	[3]	48	[3]	12	[3]
IFRS based Profit (loss) before tax	304	[3]	(1,701)	[3]	897	[3]	(1,778)	[3]
IFRS based Customer loans (Receivables)	(5,346)	[3]	(9,435)	[3]	(5,346)	[3]	(9,435)	[3]
IFRS based Assets	(1,967)	[3]	(3,404)	[3]	(1,967)	[3]	(3,404)	[3]
IFRS Reclassifications
Operating Statistics [Line Items]
IFRS based Net interest income	(87)	[4]	(104)	[4]	(170)	[4]	(219)	[4]
IFRS based Other operating income (Total other revenues)	86	[4]	116	[4]	177	[4]	251	[4]
IFRS based Total operating income (loss)	(1)	[4]	12	[4]	7	[4]	32	[4]
IFRS based Loan impairment charges (Provision for credit losses)	0	[4]	0	[4]	0	[4]	0	[4]
IFRS based Net interest income and other operating income less provision for credit losses	(1)	[4]	12	[4]	7	[4]	32	[4]
IFRS based Operating expense	(1)	[4]	12	[4]	7	[4]	32	[4]
IFRS based Profit (loss) before tax	0	[4]	0	[4]	0	[4]	0	[4]
IFRS based Customer loans (Receivables)	(40)	[4]	(47)	[4]	(40)	[4]	(47)	[4]
IFRS based Assets	$ 0	[4]	$ 0	[4]	$ 0	[4]	$ 0	[4]

[1] These amounts represent TDR Loans for which we evaluate reserves using a discounted cash flow methodology. Each loan is individually identified as a TDR Loan and then grouped together with other TDR Loans with similar characteristics. The discounted cash flow impairment analysis is then applied to these groups of TDR Loans. The receivable balance above excludes TDR Loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell which totaled $726 million and $671 million at June 30, 2013 and 2012, respectively. The reserve component above excludes credit loss reserves for TDR Loans that are carried at the lower of amortized cost or fair value of the collateral less cost to sell which totaled $51 million and $41 million at June 30, 2013 and 2012, respectively. These credit loss reserves are reflected within receivables carried at the lower of amortized cost or fair value of the collateral less cost to sell in the table above.

[2] The three and six months ended June 30, 2012 includes $112 million related to the lower of amortized cost or fair value attributable to credit for personal non-credit card receivables transferred to held for sale at June 30, 2012. See Note 6, "Receivables Held for Sale," for additional information.

[3] IFRS Adjustments consist of the accounting differences between U.S. GAAP and IFRSs which have been described more fully above.

[4] Represents differences in balance sheet and income statement presentation between U.S. GAAP and IFRSs.