Receivables Held for Sale - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended			3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended			0 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Sep. 01, 2013 employee	Sep. 30, 2014 Other Income [Member]	Sep. 30, 2013 Other Income [Member]	Sep. 30, 2014 Other Income [Member]	Sep. 30, 2013 Other Income [Member]	Sep. 30, 2014 Fair Value [Member] Other Income [Member]	Sep. 30, 2013 Fair Value [Member] Other Income [Member]	Sep. 30, 2014 Fair Value [Member] Other Income [Member]	Sep. 30, 2013 Fair Value [Member] Other Income [Member]	Sep. 30, 2014 Real Estate Owned [Member]	Sep. 30, 2013 Real Estate Owned [Member]	Sep. 30, 2014 Real Estate Owned [Member]	Sep. 30, 2013 Real Estate Owned [Member]	Sep. 30, 2014 Real Estate Owned [Member] Other Income [Member]	Sep. 30, 2013 Real Estate Owned [Member] Other Income [Member]	Sep. 30, 2014 Real Estate Owned [Member] Other Income [Member]	Sep. 30, 2013 Real Estate Owned [Member] Other Income [Member]	Sep. 30, 2014 Short Sales [Member]	Sep. 30, 2013 Short Sales [Member]	Sep. 30, 2014 Short Sales [Member]	Sep. 30, 2013 Short Sales [Member]	Sep. 30, 2014 Short Sales [Member] Other Income [Member]	Sep. 30, 2013 Short Sales [Member] Other Income [Member]	Sep. 30, 2014 Short Sales [Member] Other Income [Member]	Sep. 30, 2013 Short Sales [Member] Other Income [Member]	Sep. 30, 2014 First Mortgage [Member]	Sep. 30, 2013 First Mortgage [Member]	Sep. 30, 2014 First Mortgage [Member]	Sep. 30, 2013 First Mortgage [Member]	Dec. 31, 2013 First Mortgage [Member]	Apr. 01, 2013 Personal non-credit card [Member]	Apr. 02, 2013 Personal non-credit card [Member]	Sep. 30, 2013 Personal non-credit card [Member]	Jun. 30, 2013 Personal non-credit card [Member]	Sep. 30, 2013 Personal non-credit card [Member]	Mar. 31, 2013 Personal non-credit card [Member]	Sep. 30, 2014 Real Estate Secured [Member]	Sep. 30, 2013 Real Estate Secured [Member]	Sep. 30, 2014 Real Estate Secured [Member]	Sep. 30, 2013 Real Estate Secured [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Receivables held for sale	$ 1,840	$ 2,047																										$ 1,840		$ 1,840		$ 2,047
Aggregate unpaid balance																												302	473	1,171	3,077		3,760
Aggregate carrying balance																												236	346	910	2,101
Initial lower of amortized cost or fair value adjustment				10	46	112	145	10	46	112	145					0	0	0	0					0	0	0	0
Period of receivables sold in multiple transactions	15 months
Change in real estate secured receivable balance, including collections												43	175	160	405					16	63	47	151
Lower of amortized cost or fair value adjustment												2	(1)	4	(50)					1	(11)	2	(22)														(82)		(97)	(100)	(410)	(1,047)
Receivable sales																																						2,947
Proceeds from sale of loans held-for-sale																																		2,964
Gain (loss) on sales of loans																																				(11)
Number of employees transferred to new department (over)			200
Servicing fees																																			$ 17		$ 29